1 /* Process declarations and variables for C++ compiler. 2 Copyright (C) 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010, 4 2011 Free Software Foundation, Inc. 5 Hacked by Michael Tiemann (tiemann@cygnus.com) 6 7 This file is part of GCC. 8 9 GCC is free software; you can redistribute it and/or modify 10 it under the terms of the GNU General Public License as published by 11 the Free Software Foundation; either version 3, or (at your option) 12 any later version. 13 14 GCC is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 GNU General Public License for more details. 18 19 You should have received a copy of the GNU General Public License 20 along with GCC; see the file COPYING3. If not see 21 <http://www.gnu.org/licenses/>. */ 22 23 24 /* Process declarations and symbol lookup for C++ front end. 25 Also constructs types; the standard scalar types at initialization, 26 and structure, union, array and enum types when they are declared. */ 27 28 /* ??? not all decl nodes are given the most useful possible 29 line numbers. For example, the CONST_DECLs for enum values. */ 30 31 #include "config.h" 32 #include "system.h" 33 #include "coretypes.h" 34 #include "tm.h" 35 #include "tree.h" 36 #include "flags.h" 37 #include "cp-tree.h" 38 #include "decl.h" 39 #include "output.h" 40 #include "toplev.h" 41 #include "timevar.h" 42 #include "cpplib.h" 43 #include "target.h" 44 #include "c-family/c-common.h" 45 #include "c-family/c-objc.h" 46 #include "cgraph.h" 47 #include "tree-inline.h" 48 #include "c-family/c-pragma.h" 49 #include "tree-dump.h" 50 #include "intl.h" 51 #include "gimple.h" 52 #include "pointer-set.h" 53 #include "splay-tree.h" 54 #include "langhooks.h" 55 #include "c-family/c-ada-spec.h" 56 57 extern cpp_reader *parse_in; 58 59 /* This structure contains information about the initializations 60 and/or destructions required for a particular priority level. */ 61 typedef struct priority_info_s { 62 /* Nonzero if there have been any initializations at this priority 63 throughout the translation unit. */ 64 int initializations_p; 65 /* Nonzero if there have been any destructions at this priority 66 throughout the translation unit. */ 67 int destructions_p; 68 } *priority_info; 69 70 static void mark_vtable_entries (tree); 71 static bool maybe_emit_vtables (tree); 72 static bool acceptable_java_type (tree); 73 static tree start_objects (int, int); 74 static void finish_objects (int, int, tree); 75 static tree start_static_storage_duration_function (unsigned); 76 static void finish_static_storage_duration_function (tree); 77 static priority_info get_priority_info (int); 78 static void do_static_initialization_or_destruction (tree, bool); 79 static void one_static_initialization_or_destruction (tree, tree, bool); 80 static void generate_ctor_or_dtor_function (bool, int, location_t *); 81 static int generate_ctor_and_dtor_functions_for_priority (splay_tree_node, 82 void *); 83 static tree prune_vars_needing_no_initialization (tree *); 84 static void write_out_vars (tree); 85 static void import_export_class (tree); 86 static tree get_guard_bits (tree); 87 static void determine_visibility_from_class (tree, tree); 88 static bool determine_hidden_inline (tree); 89 static bool decl_defined_p (tree); 90 91 /* A list of static class variables. This is needed, because a 92 static class variable can be declared inside the class without 93 an initializer, and then initialized, statically, outside the class. */ 94 static GTY(()) VEC(tree,gc) *pending_statics; 95 96 /* A list of functions which were declared inline, but which we 97 may need to emit outline anyway. */ 98 static GTY(()) VEC(tree,gc) *deferred_fns; 99 100 /* A list of decls that use types with no linkage, which we need to make 101 sure are defined. */ 102 static GTY(()) VEC(tree,gc) *no_linkage_decls; 103 104 /* Nonzero if we're done parsing and into end-of-file activities. */ 105 106 int at_eof; 107 108 109 110 /* Return a member function type (a METHOD_TYPE), given FNTYPE (a 111 FUNCTION_TYPE), CTYPE (class type), and QUALS (the cv-qualifiers 112 that apply to the function). */ 113 114 tree 115 build_memfn_type (tree fntype, tree ctype, cp_cv_quals quals) 116 { 117 tree raises; 118 tree attrs; 119 int type_quals; 120 121 if (fntype == error_mark_node || ctype == error_mark_node) 122 return error_mark_node; 123 124 gcc_assert (TREE_CODE (fntype) == FUNCTION_TYPE 125 || TREE_CODE (fntype) == METHOD_TYPE); 126 127 type_quals = quals & ~TYPE_QUAL_RESTRICT; 128 ctype = cp_build_qualified_type (ctype, type_quals); 129 raises = TYPE_RAISES_EXCEPTIONS (fntype); 130 attrs = TYPE_ATTRIBUTES (fntype); 131 fntype = build_method_type_directly (ctype, TREE_TYPE (fntype), 132 (TREE_CODE (fntype) == METHOD_TYPE 133 ? TREE_CHAIN (TYPE_ARG_TYPES (fntype)) 134 : TYPE_ARG_TYPES (fntype))); 135 if (raises) 136 fntype = build_exception_variant (fntype, raises); 137 if (attrs) 138 fntype = cp_build_type_attribute_variant (fntype, attrs); 139 140 return fntype; 141 } 142 143 /* Return a variant of FNTYPE, a FUNCTION_TYPE or METHOD_TYPE, with its 144 return type changed to NEW_RET. */ 145 146 tree 147 change_return_type (tree new_ret, tree fntype) 148 { 149 tree newtype; 150 tree args = TYPE_ARG_TYPES (fntype); 151 tree raises = TYPE_RAISES_EXCEPTIONS (fntype); 152 tree attrs = TYPE_ATTRIBUTES (fntype); 153 154 if (same_type_p (new_ret, TREE_TYPE (fntype))) 155 return fntype; 156 157 if (TREE_CODE (fntype) == FUNCTION_TYPE) 158 { 159 newtype = build_function_type (new_ret, args); 160 newtype = apply_memfn_quals (newtype, type_memfn_quals (fntype)); 161 } 162 else 163 newtype = build_method_type_directly 164 (class_of_this_parm (fntype), new_ret, TREE_CHAIN (args)); 165 if (raises) 166 newtype = build_exception_variant (newtype, raises); 167 if (attrs) 168 newtype = cp_build_type_attribute_variant (newtype, attrs); 169 170 return newtype; 171 } 172 173 /* Build a PARM_DECL with NAME and TYPE, and set DECL_ARG_TYPE 174 appropriately. */ 175 176 tree 177 cp_build_parm_decl (tree name, tree type) 178 { 179 tree parm = build_decl (input_location, 180 PARM_DECL, name, type); 181 /* DECL_ARG_TYPE is only used by the back end and the back end never 182 sees templates. */ 183 if (!processing_template_decl) 184 DECL_ARG_TYPE (parm) = type_passed_as (type); 185 186 /* If the type is a pack expansion, then we have a function 187 parameter pack. */ 188 if (type && TREE_CODE (type) == TYPE_PACK_EXPANSION) 189 FUNCTION_PARAMETER_PACK_P (parm) = 1; 190 191 return parm; 192 } 193 194 /* Returns a PARM_DECL for a parameter of the indicated TYPE, with the 195 indicated NAME. */ 196 197 tree 198 build_artificial_parm (tree name, tree type) 199 { 200 tree parm = cp_build_parm_decl (name, type); 201 DECL_ARTIFICIAL (parm) = 1; 202 /* All our artificial parms are implicitly `const'; they cannot be 203 assigned to. */ 204 TREE_READONLY (parm) = 1; 205 return parm; 206 } 207 208 /* Constructors for types with virtual baseclasses need an "in-charge" flag 209 saying whether this constructor is responsible for initialization of 210 virtual baseclasses or not. All destructors also need this "in-charge" 211 flag, which additionally determines whether or not the destructor should 212 free the memory for the object. 213 214 This function adds the "in-charge" flag to member function FN if 215 appropriate. It is called from grokclassfn and tsubst. 216 FN must be either a constructor or destructor. 217 218 The in-charge flag follows the 'this' parameter, and is followed by the 219 VTT parm (if any), then the user-written parms. */ 220 221 void 222 maybe_retrofit_in_chrg (tree fn) 223 { 224 tree basetype, arg_types, parms, parm, fntype; 225 226 /* If we've already add the in-charge parameter don't do it again. */ 227 if (DECL_HAS_IN_CHARGE_PARM_P (fn)) 228 return; 229 230 /* When processing templates we can't know, in general, whether or 231 not we're going to have virtual baseclasses. */ 232 if (processing_template_decl) 233 return; 234 235 /* We don't need an in-charge parameter for constructors that don't 236 have virtual bases. */ 237 if (DECL_CONSTRUCTOR_P (fn) 238 && !CLASSTYPE_VBASECLASSES (DECL_CONTEXT (fn))) 239 return; 240 241 arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn)); 242 basetype = TREE_TYPE (TREE_VALUE (arg_types)); 243 arg_types = TREE_CHAIN (arg_types); 244 245 parms = DECL_CHAIN (DECL_ARGUMENTS (fn)); 246 247 /* If this is a subobject constructor or destructor, our caller will 248 pass us a pointer to our VTT. */ 249 if (CLASSTYPE_VBASECLASSES (DECL_CONTEXT (fn))) 250 { 251 parm = build_artificial_parm (vtt_parm_identifier, vtt_parm_type); 252 253 /* First add it to DECL_ARGUMENTS between 'this' and the real args... */ 254 DECL_CHAIN (parm) = parms; 255 parms = parm; 256 257 /* ...and then to TYPE_ARG_TYPES. */ 258 arg_types = hash_tree_chain (vtt_parm_type, arg_types); 259 260 DECL_HAS_VTT_PARM_P (fn) = 1; 261 } 262 263 /* Then add the in-charge parm (before the VTT parm). */ 264 parm = build_artificial_parm (in_charge_identifier, integer_type_node); 265 DECL_CHAIN (parm) = parms; 266 parms = parm; 267 arg_types = hash_tree_chain (integer_type_node, arg_types); 268 269 /* Insert our new parameter(s) into the list. */ 270 DECL_CHAIN (DECL_ARGUMENTS (fn)) = parms; 271 272 /* And rebuild the function type. */ 273 fntype = build_method_type_directly (basetype, TREE_TYPE (TREE_TYPE (fn)), 274 arg_types); 275 if (TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn))) 276 fntype = build_exception_variant (fntype, 277 TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn))); 278 if (TYPE_ATTRIBUTES (TREE_TYPE (fn))) 279 fntype = (cp_build_type_attribute_variant 280 (fntype, TYPE_ATTRIBUTES (TREE_TYPE (fn)))); 281 TREE_TYPE (fn) = fntype; 282 283 /* Now we've got the in-charge parameter. */ 284 DECL_HAS_IN_CHARGE_PARM_P (fn) = 1; 285 } 286 287 /* Classes overload their constituent function names automatically. 288 When a function name is declared in a record structure, 289 its name is changed to it overloaded name. Since names for 290 constructors and destructors can conflict, we place a leading 291 '$' for destructors. 292 293 CNAME is the name of the class we are grokking for. 294 295 FUNCTION is a FUNCTION_DECL. It was created by `grokdeclarator'. 296 297 FLAGS contains bits saying what's special about today's 298 arguments. DTOR_FLAG == DESTRUCTOR. 299 300 If FUNCTION is a destructor, then we must add the `auto-delete' field 301 as a second parameter. There is some hair associated with the fact 302 that we must "declare" this variable in the manner consistent with the 303 way the rest of the arguments were declared. 304 305 QUALS are the qualifiers for the this pointer. */ 306 307 void 308 grokclassfn (tree ctype, tree function, enum overload_flags flags) 309 { 310 tree fn_name = DECL_NAME (function); 311 312 /* Even within an `extern "C"' block, members get C++ linkage. See 313 [dcl.link] for details. */ 314 SET_DECL_LANGUAGE (function, lang_cplusplus); 315 316 if (fn_name == NULL_TREE) 317 { 318 error ("name missing for member function"); 319 fn_name = get_identifier ("<anonymous>"); 320 DECL_NAME (function) = fn_name; 321 } 322 323 DECL_CONTEXT (function) = ctype; 324 325 if (flags == DTOR_FLAG) 326 DECL_DESTRUCTOR_P (function) = 1; 327 328 if (flags == DTOR_FLAG || DECL_CONSTRUCTOR_P (function)) 329 maybe_retrofit_in_chrg (function); 330 } 331 332 /* Create an ARRAY_REF, checking for the user doing things backwards 333 along the way. */ 334 335 tree 336 grok_array_decl (tree array_expr, tree index_exp) 337 { 338 tree type; 339 tree expr; 340 tree orig_array_expr = array_expr; 341 tree orig_index_exp = index_exp; 342 343 if (error_operand_p (array_expr) || error_operand_p (index_exp)) 344 return error_mark_node; 345 346 if (processing_template_decl) 347 { 348 if (type_dependent_expression_p (array_expr) 349 || type_dependent_expression_p (index_exp)) 350 return build_min_nt (ARRAY_REF, array_expr, index_exp, 351 NULL_TREE, NULL_TREE); 352 array_expr = build_non_dependent_expr (array_expr); 353 index_exp = build_non_dependent_expr (index_exp); 354 } 355 356 type = TREE_TYPE (array_expr); 357 gcc_assert (type); 358 type = non_reference (type); 359 360 /* If they have an `operator[]', use that. */ 361 if (MAYBE_CLASS_TYPE_P (type) || MAYBE_CLASS_TYPE_P (TREE_TYPE (index_exp))) 362 expr = build_new_op (ARRAY_REF, LOOKUP_NORMAL, 363 array_expr, index_exp, NULL_TREE, 364 /*overload=*/NULL, tf_warning_or_error); 365 else 366 { 367 tree p1, p2, i1, i2; 368 369 /* Otherwise, create an ARRAY_REF for a pointer or array type. 370 It is a little-known fact that, if `a' is an array and `i' is 371 an int, you can write `i[a]', which means the same thing as 372 `a[i]'. */ 373 if (TREE_CODE (type) == ARRAY_TYPE) 374 p1 = array_expr; 375 else 376 p1 = build_expr_type_conversion (WANT_POINTER, array_expr, false); 377 378 if (TREE_CODE (TREE_TYPE (index_exp)) == ARRAY_TYPE) 379 p2 = index_exp; 380 else 381 p2 = build_expr_type_conversion (WANT_POINTER, index_exp, false); 382 383 i1 = build_expr_type_conversion (WANT_INT | WANT_ENUM, array_expr, 384 false); 385 i2 = build_expr_type_conversion (WANT_INT | WANT_ENUM, index_exp, 386 false); 387 388 if ((p1 && i2) && (i1 && p2)) 389 error ("ambiguous conversion for array subscript"); 390 391 if (p1 && i2) 392 array_expr = p1, index_exp = i2; 393 else if (i1 && p2) 394 array_expr = p2, index_exp = i1; 395 else 396 { 397 error ("invalid types %<%T[%T]%> for array subscript", 398 type, TREE_TYPE (index_exp)); 399 return error_mark_node; 400 } 401 402 if (array_expr == error_mark_node || index_exp == error_mark_node) 403 error ("ambiguous conversion for array subscript"); 404 405 expr = build_array_ref (input_location, array_expr, index_exp); 406 } 407 if (processing_template_decl && expr != error_mark_node) 408 return build_min_non_dep (ARRAY_REF, expr, orig_array_expr, orig_index_exp, 409 NULL_TREE, NULL_TREE); 410 return expr; 411 } 412 413 /* Given the cast expression EXP, checking out its validity. Either return 414 an error_mark_node if there was an unavoidable error, return a cast to 415 void for trying to delete a pointer w/ the value 0, or return the 416 call to delete. If DOING_VEC is true, we handle things differently 417 for doing an array delete. 418 Implements ARM $5.3.4. This is called from the parser. */ 419 420 tree 421 delete_sanity (tree exp, tree size, bool doing_vec, int use_global_delete, 422 tsubst_flags_t complain) 423 { 424 tree t, type; 425 426 if (exp == error_mark_node) 427 return exp; 428 429 if (processing_template_decl) 430 { 431 t = build_min (DELETE_EXPR, void_type_node, exp, size); 432 DELETE_EXPR_USE_GLOBAL (t) = use_global_delete; 433 DELETE_EXPR_USE_VEC (t) = doing_vec; 434 TREE_SIDE_EFFECTS (t) = 1; 435 return t; 436 } 437 438 /* An array can't have been allocated by new, so complain. */ 439 if (TREE_CODE (exp) == VAR_DECL 440 && TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE) 441 warning (0, "deleting array %q#D", exp); 442 443 t = build_expr_type_conversion (WANT_POINTER, exp, true); 444 445 if (t == NULL_TREE || t == error_mark_node) 446 { 447 error ("type %q#T argument given to %<delete%>, expected pointer", 448 TREE_TYPE (exp)); 449 return error_mark_node; 450 } 451 452 type = TREE_TYPE (t); 453 454 /* As of Valley Forge, you can delete a pointer to const. */ 455 456 /* You can't delete functions. */ 457 if (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE) 458 { 459 error ("cannot delete a function. Only pointer-to-objects are " 460 "valid arguments to %<delete%>"); 461 return error_mark_node; 462 } 463 464 /* Deleting ptr to void is undefined behavior [expr.delete/3]. */ 465 if (TREE_CODE (TREE_TYPE (type)) == VOID_TYPE) 466 { 467 warning (0, "deleting %qT is undefined", type); 468 doing_vec = 0; 469 } 470 471 /* Deleting a pointer with the value zero is valid and has no effect. */ 472 if (integer_zerop (t)) 473 return build1 (NOP_EXPR, void_type_node, t); 474 475 if (doing_vec) 476 return build_vec_delete (t, /*maxindex=*/NULL_TREE, 477 sfk_deleting_destructor, 478 use_global_delete, complain); 479 else 480 return build_delete (type, t, sfk_deleting_destructor, 481 LOOKUP_NORMAL, use_global_delete, 482 complain); 483 } 484 485 /* Report an error if the indicated template declaration is not the 486 sort of thing that should be a member template. */ 487 488 void 489 check_member_template (tree tmpl) 490 { 491 tree decl; 492 493 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL); 494 decl = DECL_TEMPLATE_RESULT (tmpl); 495 496 if (TREE_CODE (decl) == FUNCTION_DECL 497 || DECL_ALIAS_TEMPLATE_P (tmpl) 498 || (TREE_CODE (decl) == TYPE_DECL 499 && MAYBE_CLASS_TYPE_P (TREE_TYPE (decl)))) 500 { 501 /* The parser rejects template declarations in local classes. */ 502 gcc_assert (!current_function_decl); 503 /* The parser rejects any use of virtual in a function template. */ 504 gcc_assert (!(TREE_CODE (decl) == FUNCTION_DECL 505 && DECL_VIRTUAL_P (decl))); 506 507 /* The debug-information generating code doesn't know what to do 508 with member templates. */ 509 DECL_IGNORED_P (tmpl) = 1; 510 } 511 else 512 error ("template declaration of %q#D", decl); 513 } 514 515 /* Return true iff TYPE is a valid Java parameter or return type. */ 516 517 static bool 518 acceptable_java_type (tree type) 519 { 520 if (type == error_mark_node) 521 return false; 522 523 if (TREE_CODE (type) == VOID_TYPE || TYPE_FOR_JAVA (type)) 524 return true; 525 if (TREE_CODE (type) == POINTER_TYPE || TREE_CODE (type) == REFERENCE_TYPE) 526 { 527 type = TREE_TYPE (type); 528 if (TREE_CODE (type) == RECORD_TYPE) 529 { 530 tree args; int i; 531 if (! TYPE_FOR_JAVA (type)) 532 return false; 533 if (! CLASSTYPE_TEMPLATE_INFO (type)) 534 return true; 535 args = CLASSTYPE_TI_ARGS (type); 536 i = TREE_VEC_LENGTH (args); 537 while (--i >= 0) 538 { 539 type = TREE_VEC_ELT (args, i); 540 if (TREE_CODE (type) == POINTER_TYPE) 541 type = TREE_TYPE (type); 542 if (! TYPE_FOR_JAVA (type)) 543 return false; 544 } 545 return true; 546 } 547 } 548 return false; 549 } 550 551 /* For a METHOD in a Java class CTYPE, return true if 552 the parameter and return types are valid Java types. 553 Otherwise, print appropriate error messages, and return false. */ 554 555 bool 556 check_java_method (tree method) 557 { 558 bool jerr = false; 559 tree arg_types = TYPE_ARG_TYPES (TREE_TYPE (method)); 560 tree ret_type = TREE_TYPE (TREE_TYPE (method)); 561 562 if (!acceptable_java_type (ret_type)) 563 { 564 error ("Java method %qD has non-Java return type %qT", 565 method, ret_type); 566 jerr = true; 567 } 568 569 arg_types = TREE_CHAIN (arg_types); 570 if (DECL_HAS_IN_CHARGE_PARM_P (method)) 571 arg_types = TREE_CHAIN (arg_types); 572 if (DECL_HAS_VTT_PARM_P (method)) 573 arg_types = TREE_CHAIN (arg_types); 574 575 for (; arg_types != NULL_TREE; arg_types = TREE_CHAIN (arg_types)) 576 { 577 tree type = TREE_VALUE (arg_types); 578 if (!acceptable_java_type (type)) 579 { 580 if (type != error_mark_node) 581 error ("Java method %qD has non-Java parameter type %qT", 582 method, type); 583 jerr = true; 584 } 585 } 586 return !jerr; 587 } 588 589 /* Sanity check: report error if this function FUNCTION is not 590 really a member of the class (CTYPE) it is supposed to belong to. 591 TEMPLATE_PARMS is used to specify the template parameters of a member 592 template passed as FUNCTION_DECL. If the member template is passed as a 593 TEMPLATE_DECL, it can be NULL since the parameters can be extracted 594 from the declaration. If the function is not a function template, it 595 must be NULL. 596 It returns the original declaration for the function, NULL_TREE if 597 no declaration was found, error_mark_node if an error was emitted. */ 598 599 tree 600 check_classfn (tree ctype, tree function, tree template_parms) 601 { 602 int ix; 603 bool is_template; 604 tree pushed_scope; 605 606 if (DECL_USE_TEMPLATE (function) 607 && !(TREE_CODE (function) == TEMPLATE_DECL 608 && DECL_TEMPLATE_SPECIALIZATION (function)) 609 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (function))) 610 /* Since this is a specialization of a member template, 611 we're not going to find the declaration in the class. 612 For example, in: 613 614 struct S { template <typename T> void f(T); }; 615 template <> void S::f(int); 616 617 we're not going to find `S::f(int)', but there's no 618 reason we should, either. We let our callers know we didn't 619 find the method, but we don't complain. */ 620 return NULL_TREE; 621 622 /* Basic sanity check: for a template function, the template parameters 623 either were not passed, or they are the same of DECL_TEMPLATE_PARMS. */ 624 if (TREE_CODE (function) == TEMPLATE_DECL) 625 { 626 if (template_parms 627 && !comp_template_parms (template_parms, 628 DECL_TEMPLATE_PARMS (function))) 629 { 630 error ("template parameter lists provided don%'t match the " 631 "template parameters of %qD", function); 632 return error_mark_node; 633 } 634 template_parms = DECL_TEMPLATE_PARMS (function); 635 } 636 637 /* OK, is this a definition of a member template? */ 638 is_template = (template_parms != NULL_TREE); 639 640 /* We must enter the scope here, because conversion operators are 641 named by target type, and type equivalence relies on typenames 642 resolving within the scope of CTYPE. */ 643 pushed_scope = push_scope (ctype); 644 ix = class_method_index_for_fn (complete_type (ctype), function); 645 if (ix >= 0) 646 { 647 VEC(tree,gc) *methods = CLASSTYPE_METHOD_VEC (ctype); 648 tree fndecls, fndecl = 0; 649 bool is_conv_op; 650 const char *format = NULL; 651 652 for (fndecls = VEC_index (tree, methods, ix); 653 fndecls; fndecls = OVL_NEXT (fndecls)) 654 { 655 tree p1, p2; 656 657 fndecl = OVL_CURRENT (fndecls); 658 p1 = TYPE_ARG_TYPES (TREE_TYPE (function)); 659 p2 = TYPE_ARG_TYPES (TREE_TYPE (fndecl)); 660 661 /* We cannot simply call decls_match because this doesn't 662 work for static member functions that are pretending to 663 be methods, and because the name may have been changed by 664 asm("new_name"). */ 665 666 /* Get rid of the this parameter on functions that become 667 static. */ 668 if (DECL_STATIC_FUNCTION_P (fndecl) 669 && TREE_CODE (TREE_TYPE (function)) == METHOD_TYPE) 670 p1 = TREE_CHAIN (p1); 671 672 /* A member template definition only matches a member template 673 declaration. */ 674 if (is_template != (TREE_CODE (fndecl) == TEMPLATE_DECL)) 675 continue; 676 677 if (same_type_p (TREE_TYPE (TREE_TYPE (function)), 678 TREE_TYPE (TREE_TYPE (fndecl))) 679 && compparms (p1, p2) 680 && (!is_template 681 || comp_template_parms (template_parms, 682 DECL_TEMPLATE_PARMS (fndecl))) 683 && (DECL_TEMPLATE_SPECIALIZATION (function) 684 == DECL_TEMPLATE_SPECIALIZATION (fndecl)) 685 && (!DECL_TEMPLATE_SPECIALIZATION (function) 686 || (DECL_TI_TEMPLATE (function) 687 == DECL_TI_TEMPLATE (fndecl)))) 688 break; 689 } 690 if (fndecls) 691 { 692 if (pushed_scope) 693 pop_scope (pushed_scope); 694 return OVL_CURRENT (fndecls); 695 } 696 697 error_at (DECL_SOURCE_LOCATION (function), 698 "prototype for %q#D does not match any in class %qT", 699 function, ctype); 700 is_conv_op = DECL_CONV_FN_P (fndecl); 701 702 if (is_conv_op) 703 ix = CLASSTYPE_FIRST_CONVERSION_SLOT; 704 fndecls = VEC_index (tree, methods, ix); 705 while (fndecls) 706 { 707 fndecl = OVL_CURRENT (fndecls); 708 fndecls = OVL_NEXT (fndecls); 709 710 if (!fndecls && is_conv_op) 711 { 712 if (VEC_length (tree, methods) > (size_t) ++ix) 713 { 714 fndecls = VEC_index (tree, methods, ix); 715 if (!DECL_CONV_FN_P (OVL_CURRENT (fndecls))) 716 { 717 fndecls = NULL_TREE; 718 is_conv_op = false; 719 } 720 } 721 else 722 is_conv_op = false; 723 } 724 if (format) 725 format = " %+#D"; 726 else if (fndecls) 727 format = N_("candidates are: %+#D"); 728 else 729 format = N_("candidate is: %+#D"); 730 error (format, fndecl); 731 } 732 } 733 else if (!COMPLETE_TYPE_P (ctype)) 734 cxx_incomplete_type_error (function, ctype); 735 else 736 error ("no %q#D member function declared in class %qT", 737 function, ctype); 738 739 if (pushed_scope) 740 pop_scope (pushed_scope); 741 return error_mark_node; 742 } 743 744 /* DECL is a function with vague linkage. Remember it so that at the 745 end of the translation unit we can decide whether or not to emit 746 it. */ 747 748 void 749 note_vague_linkage_fn (tree decl) 750 { 751 DECL_DEFER_OUTPUT (decl) = 1; 752 VEC_safe_push (tree, gc, deferred_fns, decl); 753 } 754 755 /* We have just processed the DECL, which is a static data member. 756 The other parameters are as for cp_finish_decl. */ 757 758 void 759 finish_static_data_member_decl (tree decl, 760 tree init, bool init_const_expr_p, 761 tree asmspec_tree, 762 int flags) 763 { 764 DECL_CONTEXT (decl) = current_class_type; 765 766 /* We cannot call pushdecl here, because that would fill in the 767 TREE_CHAIN of our decl. Instead, we modify cp_finish_decl to do 768 the right thing, namely, to put this decl out straight away. */ 769 770 if (! processing_template_decl) 771 VEC_safe_push (tree, gc, pending_statics, decl); 772 773 if (LOCAL_CLASS_P (current_class_type)) 774 permerror (input_location, "local class %q#T shall not have static data member %q#D", 775 current_class_type, decl); 776 777 DECL_IN_AGGR_P (decl) = 1; 778 779 if (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE 780 && TYPE_DOMAIN (TREE_TYPE (decl)) == NULL_TREE) 781 SET_VAR_HAD_UNKNOWN_BOUND (decl); 782 783 cp_finish_decl (decl, init, init_const_expr_p, asmspec_tree, flags); 784 } 785 786 /* DECLARATOR and DECLSPECS correspond to a class member. The other 787 parameters are as for cp_finish_decl. Return the DECL for the 788 class member declared. */ 789 790 tree 791 grokfield (const cp_declarator *declarator, 792 cp_decl_specifier_seq *declspecs, 793 tree init, bool init_const_expr_p, 794 tree asmspec_tree, 795 tree attrlist) 796 { 797 tree value; 798 const char *asmspec = 0; 799 int flags; 800 tree name; 801 802 if (init 803 && TREE_CODE (init) == TREE_LIST 804 && TREE_VALUE (init) == error_mark_node 805 && TREE_CHAIN (init) == NULL_TREE) 806 init = NULL_TREE; 807 808 value = grokdeclarator (declarator, declspecs, FIELD, init != 0, &attrlist); 809 if (! value || error_operand_p (value)) 810 /* friend or constructor went bad. */ 811 return error_mark_node; 812 813 if (TREE_CODE (value) == TYPE_DECL && init) 814 { 815 error ("typedef %qD is initialized (use decltype instead)", value); 816 init = NULL_TREE; 817 } 818 819 /* Pass friendly classes back. */ 820 if (value == void_type_node) 821 return value; 822 823 /* Pass friend decls back. */ 824 if ((TREE_CODE (value) == FUNCTION_DECL 825 || TREE_CODE (value) == TEMPLATE_DECL) 826 && DECL_CONTEXT (value) != current_class_type) 827 return value; 828 829 name = DECL_NAME (value); 830 831 if (name != NULL_TREE) 832 { 833 if (TREE_CODE (name) == TEMPLATE_ID_EXPR) 834 { 835 error ("explicit template argument list not allowed"); 836 return error_mark_node; 837 } 838 839 if (IDENTIFIER_POINTER (name)[0] == '_' 840 && ! strcmp (IDENTIFIER_POINTER (name), "_vptr")) 841 error ("member %qD conflicts with virtual function table field name", 842 value); 843 } 844 845 /* Stash away type declarations. */ 846 if (TREE_CODE (value) == TYPE_DECL) 847 { 848 DECL_NONLOCAL (value) = 1; 849 DECL_CONTEXT (value) = current_class_type; 850 851 if (attrlist) 852 { 853 int attrflags = 0; 854 855 /* If this is a typedef that names the class for linkage purposes 856 (7.1.3p8), apply any attributes directly to the type. */ 857 if (TAGGED_TYPE_P (TREE_TYPE (value)) 858 && value == TYPE_NAME (TYPE_MAIN_VARIANT (TREE_TYPE (value)))) 859 attrflags = ATTR_FLAG_TYPE_IN_PLACE; 860 861 cplus_decl_attributes (&value, attrlist, attrflags); 862 } 863 864 if (declspecs->specs[(int)ds_typedef] 865 && TREE_TYPE (value) != error_mark_node 866 && TYPE_NAME (TYPE_MAIN_VARIANT (TREE_TYPE (value))) != value) 867 set_underlying_type (value); 868 869 /* It's important that push_template_decl below follows 870 set_underlying_type above so that the created template 871 carries the properly set type of VALUE. */ 872 if (processing_template_decl) 873 value = push_template_decl (value); 874 875 record_locally_defined_typedef (value); 876 return value; 877 } 878 879 if (DECL_IN_AGGR_P (value)) 880 { 881 error ("%qD is already defined in %qT", value, DECL_CONTEXT (value)); 882 return void_type_node; 883 } 884 885 if (asmspec_tree && asmspec_tree != error_mark_node) 886 asmspec = TREE_STRING_POINTER (asmspec_tree); 887 888 if (init) 889 { 890 if (TREE_CODE (value) == FUNCTION_DECL) 891 { 892 /* Initializers for functions are rejected early in the parser. 893 If we get here, it must be a pure specifier for a method. */ 894 if (init == ridpointers[(int)RID_DELETE]) 895 { 896 DECL_DELETED_FN (value) = 1; 897 DECL_DECLARED_INLINE_P (value) = 1; 898 DECL_INITIAL (value) = error_mark_node; 899 } 900 else if (init == ridpointers[(int)RID_DEFAULT]) 901 { 902 if (defaultable_fn_check (value)) 903 { 904 DECL_DEFAULTED_FN (value) = 1; 905 DECL_INITIALIZED_IN_CLASS_P (value) = 1; 906 DECL_DECLARED_INLINE_P (value) = 1; 907 } 908 } 909 else if (TREE_CODE (init) == DEFAULT_ARG) 910 error ("invalid initializer for member function %qD", value); 911 else if (TREE_CODE (TREE_TYPE (value)) == METHOD_TYPE) 912 { 913 if (integer_zerop (init)) 914 DECL_PURE_VIRTUAL_P (value) = 1; 915 else if (error_operand_p (init)) 916 ; /* An error has already been reported. */ 917 else 918 error ("invalid initializer for member function %qD", 919 value); 920 } 921 else 922 { 923 gcc_assert (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE); 924 error ("initializer specified for static member function %qD", 925 value); 926 } 927 } 928 else if (TREE_CODE (value) == FIELD_DECL) 929 /* C++11 NSDMI, keep going. */; 930 else if (TREE_CODE (value) != VAR_DECL) 931 gcc_unreachable (); 932 else if (!processing_template_decl) 933 { 934 if (TREE_CODE (init) == CONSTRUCTOR) 935 init = digest_init (TREE_TYPE (value), init, tf_warning_or_error); 936 init = maybe_constant_init (init); 937 938 if (init != error_mark_node && !TREE_CONSTANT (init)) 939 { 940 /* We can allow references to things that are effectively 941 static, since references are initialized with the 942 address. */ 943 if (TREE_CODE (TREE_TYPE (value)) != REFERENCE_TYPE 944 || (TREE_STATIC (init) == 0 945 && (!DECL_P (init) || DECL_EXTERNAL (init) == 0))) 946 { 947 error ("field initializer is not constant"); 948 init = error_mark_node; 949 } 950 } 951 } 952 } 953 954 if (processing_template_decl 955 && (TREE_CODE (value) == VAR_DECL || TREE_CODE (value) == FUNCTION_DECL)) 956 { 957 value = push_template_decl (value); 958 if (error_operand_p (value)) 959 return error_mark_node; 960 } 961 962 if (attrlist) 963 cplus_decl_attributes (&value, attrlist, 0); 964 965 if (init && BRACE_ENCLOSED_INITIALIZER_P (init) 966 && CONSTRUCTOR_IS_DIRECT_INIT (init)) 967 flags = LOOKUP_NORMAL; 968 else 969 flags = LOOKUP_IMPLICIT; 970 971 switch (TREE_CODE (value)) 972 { 973 case VAR_DECL: 974 finish_static_data_member_decl (value, init, init_const_expr_p, 975 asmspec_tree, flags); 976 return value; 977 978 case FIELD_DECL: 979 if (asmspec) 980 error ("%<asm%> specifiers are not permitted on non-static data members"); 981 if (DECL_INITIAL (value) == error_mark_node) 982 init = error_mark_node; 983 cp_finish_decl (value, init, /*init_const_expr_p=*/false, 984 NULL_TREE, flags); 985 DECL_IN_AGGR_P (value) = 1; 986 return value; 987 988 case FUNCTION_DECL: 989 if (asmspec) 990 set_user_assembler_name (value, asmspec); 991 992 cp_finish_decl (value, 993 /*init=*/NULL_TREE, 994 /*init_const_expr_p=*/false, 995 asmspec_tree, flags); 996 997 /* Pass friends back this way. */ 998 if (DECL_FRIEND_P (value)) 999 return void_type_node; 1000 1001 DECL_IN_AGGR_P (value) = 1; 1002 return value; 1003 1004 default: 1005 gcc_unreachable (); 1006 } 1007 return NULL_TREE; 1008 } 1009 1010 /* Like `grokfield', but for bitfields. 1011 WIDTH is non-NULL for bit fields only, and is an INTEGER_CST node. */ 1012 1013 tree 1014 grokbitfield (const cp_declarator *declarator, 1015 cp_decl_specifier_seq *declspecs, tree width, 1016 tree attrlist) 1017 { 1018 tree value = grokdeclarator (declarator, declspecs, BITFIELD, 0, &attrlist); 1019 1020 if (value == error_mark_node) 1021 return NULL_TREE; /* friends went bad. */ 1022 1023 /* Pass friendly classes back. */ 1024 if (TREE_CODE (value) == VOID_TYPE) 1025 return void_type_node; 1026 1027 if (!INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (value)) 1028 && (POINTER_TYPE_P (value) 1029 || !dependent_type_p (TREE_TYPE (value)))) 1030 { 1031 error ("bit-field %qD with non-integral type", value); 1032 return error_mark_node; 1033 } 1034 1035 if (TREE_CODE (value) == TYPE_DECL) 1036 { 1037 error ("cannot declare %qD to be a bit-field type", value); 1038 return NULL_TREE; 1039 } 1040 1041 /* Usually, finish_struct_1 catches bitfields with invalid types. 1042 But, in the case of bitfields with function type, we confuse 1043 ourselves into thinking they are member functions, so we must 1044 check here. */ 1045 if (TREE_CODE (value) == FUNCTION_DECL) 1046 { 1047 error ("cannot declare bit-field %qD with function type", 1048 DECL_NAME (value)); 1049 return NULL_TREE; 1050 } 1051 1052 if (DECL_IN_AGGR_P (value)) 1053 { 1054 error ("%qD is already defined in the class %qT", value, 1055 DECL_CONTEXT (value)); 1056 return void_type_node; 1057 } 1058 1059 if (TREE_STATIC (value)) 1060 { 1061 error ("static member %qD cannot be a bit-field", value); 1062 return NULL_TREE; 1063 } 1064 cp_finish_decl (value, NULL_TREE, false, NULL_TREE, 0); 1065 1066 if (width != error_mark_node) 1067 { 1068 /* The width must be an integer type. */ 1069 if (!type_dependent_expression_p (width) 1070 && !INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (width))) 1071 error ("width of bit-field %qD has non-integral type %qT", value, 1072 TREE_TYPE (width)); 1073 DECL_INITIAL (value) = width; 1074 SET_DECL_C_BIT_FIELD (value); 1075 } 1076 1077 DECL_IN_AGGR_P (value) = 1; 1078 1079 if (attrlist) 1080 cplus_decl_attributes (&value, attrlist, /*flags=*/0); 1081 1082 return value; 1083 } 1084 1085 1086 /* Returns true iff ATTR is an attribute which needs to be applied at 1087 instantiation time rather than template definition time. */ 1088 1089 static bool 1090 is_late_template_attribute (tree attr, tree decl) 1091 { 1092 tree name = TREE_PURPOSE (attr); 1093 tree args = TREE_VALUE (attr); 1094 const struct attribute_spec *spec = lookup_attribute_spec (name); 1095 tree arg; 1096 1097 if (!spec) 1098 /* Unknown attribute. */ 1099 return false; 1100 1101 /* Attribute weak handling wants to write out assembly right away. */ 1102 if (is_attribute_p ("weak", name)) 1103 return true; 1104 1105 /* If any of the arguments are dependent expressions, we can't evaluate 1106 the attribute until instantiation time. */ 1107 for (arg = args; arg; arg = TREE_CHAIN (arg)) 1108 { 1109 tree t = TREE_VALUE (arg); 1110 1111 /* If the first attribute argument is an identifier, only consider 1112 second and following arguments. Attributes like mode, format, 1113 cleanup and several target specific attributes aren't late 1114 just because they have an IDENTIFIER_NODE as first argument. */ 1115 if (arg == args && TREE_CODE (t) == IDENTIFIER_NODE) 1116 continue; 1117 1118 if (value_dependent_expression_p (t) 1119 || type_dependent_expression_p (t)) 1120 return true; 1121 } 1122 1123 if (TREE_CODE (decl) == TYPE_DECL 1124 || TYPE_P (decl) 1125 || spec->type_required) 1126 { 1127 tree type = TYPE_P (decl) ? decl : TREE_TYPE (decl); 1128 1129 /* We can't apply any attributes to a completely unknown type until 1130 instantiation time. */ 1131 enum tree_code code = TREE_CODE (type); 1132 if (code == TEMPLATE_TYPE_PARM 1133 || code == BOUND_TEMPLATE_TEMPLATE_PARM 1134 || code == TYPENAME_TYPE) 1135 return true; 1136 /* Also defer most attributes on dependent types. This is not 1137 necessary in all cases, but is the better default. */ 1138 else if (dependent_type_p (type) 1139 /* But attribute visibility specifically works on 1140 templates. */ 1141 && !is_attribute_p ("visibility", name)) 1142 return true; 1143 else 1144 return false; 1145 } 1146 else 1147 return false; 1148 } 1149 1150 /* ATTR_P is a list of attributes. Remove any attributes which need to be 1151 applied at instantiation time and return them. If IS_DEPENDENT is true, 1152 the declaration itself is dependent, so all attributes should be applied 1153 at instantiation time. */ 1154 1155 static tree 1156 splice_template_attributes (tree *attr_p, tree decl) 1157 { 1158 tree *p = attr_p; 1159 tree late_attrs = NULL_TREE; 1160 tree *q = &late_attrs; 1161 1162 if (!p) 1163 return NULL_TREE; 1164 1165 for (; *p; ) 1166 { 1167 if (is_late_template_attribute (*p, decl)) 1168 { 1169 ATTR_IS_DEPENDENT (*p) = 1; 1170 *q = *p; 1171 *p = TREE_CHAIN (*p); 1172 q = &TREE_CHAIN (*q); 1173 *q = NULL_TREE; 1174 } 1175 else 1176 p = &TREE_CHAIN (*p); 1177 } 1178 1179 return late_attrs; 1180 } 1181 1182 /* Remove any late attributes from the list in ATTR_P and attach them to 1183 DECL_P. */ 1184 1185 static void 1186 save_template_attributes (tree *attr_p, tree *decl_p) 1187 { 1188 tree late_attrs = splice_template_attributes (attr_p, *decl_p); 1189 tree *q; 1190 tree old_attrs = NULL_TREE; 1191 1192 if (!late_attrs) 1193 return; 1194 1195 if (DECL_P (*decl_p)) 1196 q = &DECL_ATTRIBUTES (*decl_p); 1197 else 1198 q = &TYPE_ATTRIBUTES (*decl_p); 1199 1200 old_attrs = *q; 1201 1202 /* Merge the late attributes at the beginning with the attribute 1203 list. */ 1204 late_attrs = merge_attributes (late_attrs, *q); 1205 *q = late_attrs; 1206 1207 if (!DECL_P (*decl_p) && *decl_p == TYPE_MAIN_VARIANT (*decl_p)) 1208 { 1209 /* We've added new attributes directly to the main variant, so 1210 now we need to update all of the other variants to include 1211 these new attributes. */ 1212 tree variant; 1213 for (variant = TYPE_NEXT_VARIANT (*decl_p); variant; 1214 variant = TYPE_NEXT_VARIANT (variant)) 1215 { 1216 gcc_assert (TYPE_ATTRIBUTES (variant) == old_attrs); 1217 TYPE_ATTRIBUTES (variant) = TYPE_ATTRIBUTES (*decl_p); 1218 } 1219 } 1220 } 1221 1222 /* Like reconstruct_complex_type, but handle also template trees. */ 1223 1224 tree 1225 cp_reconstruct_complex_type (tree type, tree bottom) 1226 { 1227 tree inner, outer; 1228 1229 if (TREE_CODE (type) == POINTER_TYPE) 1230 { 1231 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom); 1232 outer = build_pointer_type_for_mode (inner, TYPE_MODE (type), 1233 TYPE_REF_CAN_ALIAS_ALL (type)); 1234 } 1235 else if (TREE_CODE (type) == REFERENCE_TYPE) 1236 { 1237 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom); 1238 outer = build_reference_type_for_mode (inner, TYPE_MODE (type), 1239 TYPE_REF_CAN_ALIAS_ALL (type)); 1240 } 1241 else if (TREE_CODE (type) == ARRAY_TYPE) 1242 { 1243 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom); 1244 outer = build_cplus_array_type (inner, TYPE_DOMAIN (type)); 1245 /* Don't call cp_build_qualified_type on ARRAY_TYPEs, the 1246 element type qualification will be handled by the recursive 1247 cp_reconstruct_complex_type call and cp_build_qualified_type 1248 for ARRAY_TYPEs changes the element type. */ 1249 return outer; 1250 } 1251 else if (TREE_CODE (type) == FUNCTION_TYPE) 1252 { 1253 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom); 1254 outer = build_function_type (inner, TYPE_ARG_TYPES (type)); 1255 outer = apply_memfn_quals (outer, type_memfn_quals (type)); 1256 } 1257 else if (TREE_CODE (type) == METHOD_TYPE) 1258 { 1259 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom); 1260 /* The build_method_type_directly() routine prepends 'this' to argument list, 1261 so we must compensate by getting rid of it. */ 1262 outer 1263 = build_method_type_directly 1264 (class_of_this_parm (type), inner, 1265 TREE_CHAIN (TYPE_ARG_TYPES (type))); 1266 } 1267 else if (TREE_CODE (type) == OFFSET_TYPE) 1268 { 1269 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom); 1270 outer = build_offset_type (TYPE_OFFSET_BASETYPE (type), inner); 1271 } 1272 else 1273 return bottom; 1274 1275 if (TYPE_ATTRIBUTES (type)) 1276 outer = cp_build_type_attribute_variant (outer, TYPE_ATTRIBUTES (type)); 1277 return cp_build_qualified_type (outer, cp_type_quals (type)); 1278 } 1279 1280 /* Replaces any constexpr expression that may be into the attributes 1281 arguments with their reduced value. */ 1282 1283 static void 1284 cp_check_const_attributes (tree attributes) 1285 { 1286 tree attr; 1287 for (attr = attributes; attr; attr = TREE_CHAIN (attr)) 1288 { 1289 tree arg; 1290 for (arg = TREE_VALUE (attr); arg; arg = TREE_CHAIN (arg)) 1291 { 1292 tree expr = TREE_VALUE (arg); 1293 if (EXPR_P (expr)) 1294 TREE_VALUE (arg) = maybe_constant_value (expr); 1295 } 1296 } 1297 } 1298 1299 /* Like decl_attributes, but handle C++ complexity. */ 1300 1301 void 1302 cplus_decl_attributes (tree *decl, tree attributes, int flags) 1303 { 1304 if (*decl == NULL_TREE || *decl == void_type_node 1305 || *decl == error_mark_node 1306 || attributes == NULL_TREE) 1307 return; 1308 1309 if (processing_template_decl) 1310 { 1311 if (check_for_bare_parameter_packs (attributes)) 1312 return; 1313 1314 save_template_attributes (&attributes, decl); 1315 if (attributes == NULL_TREE) 1316 return; 1317 } 1318 1319 cp_check_const_attributes (attributes); 1320 1321 if (TREE_CODE (*decl) == TEMPLATE_DECL) 1322 decl = &DECL_TEMPLATE_RESULT (*decl); 1323 1324 decl_attributes (decl, attributes, flags); 1325 1326 if (TREE_CODE (*decl) == TYPE_DECL) 1327 SET_IDENTIFIER_TYPE_VALUE (DECL_NAME (*decl), TREE_TYPE (*decl)); 1328 } 1329 1330 /* Walks through the namespace- or function-scope anonymous union 1331 OBJECT, with the indicated TYPE, building appropriate VAR_DECLs. 1332 Returns one of the fields for use in the mangled name. */ 1333 1334 static tree 1335 build_anon_union_vars (tree type, tree object) 1336 { 1337 tree main_decl = NULL_TREE; 1338 tree field; 1339 1340 /* Rather than write the code to handle the non-union case, 1341 just give an error. */ 1342 if (TREE_CODE (type) != UNION_TYPE) 1343 { 1344 error ("anonymous struct not inside named type"); 1345 return error_mark_node; 1346 } 1347 1348 for (field = TYPE_FIELDS (type); 1349 field != NULL_TREE; 1350 field = DECL_CHAIN (field)) 1351 { 1352 tree decl; 1353 tree ref; 1354 1355 if (DECL_ARTIFICIAL (field)) 1356 continue; 1357 if (TREE_CODE (field) != FIELD_DECL) 1358 { 1359 permerror (input_location, "%q+#D invalid; an anonymous union can only " 1360 "have non-static data members", field); 1361 continue; 1362 } 1363 1364 if (TREE_PRIVATE (field)) 1365 permerror (input_location, "private member %q+#D in anonymous union", field); 1366 else if (TREE_PROTECTED (field)) 1367 permerror (input_location, "protected member %q+#D in anonymous union", field); 1368 1369 if (processing_template_decl) 1370 ref = build_min_nt (COMPONENT_REF, object, 1371 DECL_NAME (field), NULL_TREE); 1372 else 1373 ref = build_class_member_access_expr (object, field, NULL_TREE, 1374 false, tf_warning_or_error); 1375 1376 if (DECL_NAME (field)) 1377 { 1378 tree base; 1379 1380 decl = build_decl (input_location, 1381 VAR_DECL, DECL_NAME (field), TREE_TYPE (field)); 1382 DECL_ANON_UNION_VAR_P (decl) = 1; 1383 DECL_ARTIFICIAL (decl) = 1; 1384 1385 base = get_base_address (object); 1386 TREE_PUBLIC (decl) = TREE_PUBLIC (base); 1387 TREE_STATIC (decl) = TREE_STATIC (base); 1388 DECL_EXTERNAL (decl) = DECL_EXTERNAL (base); 1389 1390 SET_DECL_VALUE_EXPR (decl, ref); 1391 DECL_HAS_VALUE_EXPR_P (decl) = 1; 1392 1393 decl = pushdecl (decl); 1394 } 1395 else if (ANON_AGGR_TYPE_P (TREE_TYPE (field))) 1396 decl = build_anon_union_vars (TREE_TYPE (field), ref); 1397 else 1398 decl = 0; 1399 1400 if (main_decl == NULL_TREE) 1401 main_decl = decl; 1402 } 1403 1404 return main_decl; 1405 } 1406 1407 /* Finish off the processing of a UNION_TYPE structure. If the union is an 1408 anonymous union, then all members must be laid out together. PUBLIC_P 1409 is nonzero if this union is not declared static. */ 1410 1411 void 1412 finish_anon_union (tree anon_union_decl) 1413 { 1414 tree type; 1415 tree main_decl; 1416 bool public_p; 1417 1418 if (anon_union_decl == error_mark_node) 1419 return; 1420 1421 type = TREE_TYPE (anon_union_decl); 1422 public_p = TREE_PUBLIC (anon_union_decl); 1423 1424 /* The VAR_DECL's context is the same as the TYPE's context. */ 1425 DECL_CONTEXT (anon_union_decl) = DECL_CONTEXT (TYPE_NAME (type)); 1426 1427 if (TYPE_FIELDS (type) == NULL_TREE) 1428 return; 1429 1430 if (public_p) 1431 { 1432 error ("namespace-scope anonymous aggregates must be static"); 1433 return; 1434 } 1435 1436 main_decl = build_anon_union_vars (type, anon_union_decl); 1437 if (main_decl == error_mark_node) 1438 return; 1439 if (main_decl == NULL_TREE) 1440 { 1441 warning (0, "anonymous union with no members"); 1442 return; 1443 } 1444 1445 if (!processing_template_decl) 1446 { 1447 /* Use main_decl to set the mangled name. */ 1448 DECL_NAME (anon_union_decl) = DECL_NAME (main_decl); 1449 maybe_commonize_var (anon_union_decl); 1450 if (TREE_STATIC (anon_union_decl) || DECL_EXTERNAL (anon_union_decl)) 1451 mangle_decl (anon_union_decl); 1452 DECL_NAME (anon_union_decl) = NULL_TREE; 1453 } 1454 1455 pushdecl (anon_union_decl); 1456 if (building_stmt_list_p () 1457 && at_function_scope_p ()) 1458 add_decl_expr (anon_union_decl); 1459 else if (!processing_template_decl) 1460 rest_of_decl_compilation (anon_union_decl, 1461 toplevel_bindings_p (), at_eof); 1462 } 1463 1464 /* Auxiliary functions to make type signatures for 1465 `operator new' and `operator delete' correspond to 1466 what compiler will be expecting. */ 1467 1468 tree 1469 coerce_new_type (tree type) 1470 { 1471 int e = 0; 1472 tree args = TYPE_ARG_TYPES (type); 1473 1474 gcc_assert (TREE_CODE (type) == FUNCTION_TYPE); 1475 1476 if (!same_type_p (TREE_TYPE (type), ptr_type_node)) 1477 { 1478 e = 1; 1479 error ("%<operator new%> must return type %qT", ptr_type_node); 1480 } 1481 1482 if (args && args != void_list_node) 1483 { 1484 if (TREE_PURPOSE (args)) 1485 { 1486 /* [basic.stc.dynamic.allocation] 1487 1488 The first parameter shall not have an associated default 1489 argument. */ 1490 error ("the first parameter of %<operator new%> cannot " 1491 "have a default argument"); 1492 /* Throw away the default argument. */ 1493 TREE_PURPOSE (args) = NULL_TREE; 1494 } 1495 1496 if (!same_type_p (TREE_VALUE (args), size_type_node)) 1497 { 1498 e = 2; 1499 args = TREE_CHAIN (args); 1500 } 1501 } 1502 else 1503 e = 2; 1504 1505 if (e == 2) 1506 permerror (input_location, "%<operator new%> takes type %<size_t%> (%qT) " 1507 "as first parameter", size_type_node); 1508 1509 switch (e) 1510 { 1511 case 2: 1512 args = tree_cons (NULL_TREE, size_type_node, args); 1513 /* Fall through. */ 1514 case 1: 1515 type = build_exception_variant 1516 (build_function_type (ptr_type_node, args), 1517 TYPE_RAISES_EXCEPTIONS (type)); 1518 /* Fall through. */ 1519 default:; 1520 } 1521 return type; 1522 } 1523 1524 tree 1525 coerce_delete_type (tree type) 1526 { 1527 int e = 0; 1528 tree args = TYPE_ARG_TYPES (type); 1529 1530 gcc_assert (TREE_CODE (type) == FUNCTION_TYPE); 1531 1532 if (!same_type_p (TREE_TYPE (type), void_type_node)) 1533 { 1534 e = 1; 1535 error ("%<operator delete%> must return type %qT", void_type_node); 1536 } 1537 1538 if (!args || args == void_list_node 1539 || !same_type_p (TREE_VALUE (args), ptr_type_node)) 1540 { 1541 e = 2; 1542 if (args && args != void_list_node) 1543 args = TREE_CHAIN (args); 1544 error ("%<operator delete%> takes type %qT as first parameter", 1545 ptr_type_node); 1546 } 1547 switch (e) 1548 { 1549 case 2: 1550 args = tree_cons (NULL_TREE, ptr_type_node, args); 1551 /* Fall through. */ 1552 case 1: 1553 type = build_exception_variant 1554 (build_function_type (void_type_node, args), 1555 TYPE_RAISES_EXCEPTIONS (type)); 1556 /* Fall through. */ 1557 default:; 1558 } 1559 1560 return type; 1561 } 1562 1563 /* DECL is a VAR_DECL for a vtable: walk through the entries in the vtable 1564 and mark them as needed. */ 1565 1566 static void 1567 mark_vtable_entries (tree decl) 1568 { 1569 tree fnaddr; 1570 unsigned HOST_WIDE_INT idx; 1571 1572 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)), 1573 idx, fnaddr) 1574 { 1575 tree fn; 1576 1577 STRIP_NOPS (fnaddr); 1578 1579 if (TREE_CODE (fnaddr) != ADDR_EXPR 1580 && TREE_CODE (fnaddr) != FDESC_EXPR) 1581 /* This entry is an offset: a virtual base class offset, a 1582 virtual call offset, an RTTI offset, etc. */ 1583 continue; 1584 1585 fn = TREE_OPERAND (fnaddr, 0); 1586 TREE_ADDRESSABLE (fn) = 1; 1587 /* When we don't have vcall offsets, we output thunks whenever 1588 we output the vtables that contain them. With vcall offsets, 1589 we know all the thunks we'll need when we emit a virtual 1590 function, so we emit the thunks there instead. */ 1591 if (DECL_THUNK_P (fn)) 1592 use_thunk (fn, /*emit_p=*/0); 1593 mark_used (fn); 1594 } 1595 } 1596 1597 /* Set DECL up to have the closest approximation of "initialized common" 1598 linkage available. */ 1599 1600 void 1601 comdat_linkage (tree decl) 1602 { 1603 if (flag_weak) 1604 make_decl_one_only (decl, cxx_comdat_group (decl)); 1605 else if (TREE_CODE (decl) == FUNCTION_DECL 1606 || (TREE_CODE (decl) == VAR_DECL && DECL_ARTIFICIAL (decl))) 1607 /* We can just emit function and compiler-generated variables 1608 statically; having multiple copies is (for the most part) only 1609 a waste of space. 1610 1611 There are two correctness issues, however: the address of a 1612 template instantiation with external linkage should be the 1613 same, independent of what translation unit asks for the 1614 address, and this will not hold when we emit multiple copies of 1615 the function. However, there's little else we can do. 1616 1617 Also, by default, the typeinfo implementation assumes that 1618 there will be only one copy of the string used as the name for 1619 each type. Therefore, if weak symbols are unavailable, the 1620 run-time library should perform a more conservative check; it 1621 should perform a string comparison, rather than an address 1622 comparison. */ 1623 TREE_PUBLIC (decl) = 0; 1624 else 1625 { 1626 /* Static data member template instantiations, however, cannot 1627 have multiple copies. */ 1628 if (DECL_INITIAL (decl) == 0 1629 || DECL_INITIAL (decl) == error_mark_node) 1630 DECL_COMMON (decl) = 1; 1631 else if (EMPTY_CONSTRUCTOR_P (DECL_INITIAL (decl))) 1632 { 1633 DECL_COMMON (decl) = 1; 1634 DECL_INITIAL (decl) = error_mark_node; 1635 } 1636 else if (!DECL_EXPLICIT_INSTANTIATION (decl)) 1637 { 1638 /* We can't do anything useful; leave vars for explicit 1639 instantiation. */ 1640 DECL_EXTERNAL (decl) = 1; 1641 DECL_NOT_REALLY_EXTERN (decl) = 0; 1642 } 1643 } 1644 1645 DECL_COMDAT (decl) = 1; 1646 } 1647 1648 /* For win32 we also want to put explicit instantiations in 1649 linkonce sections, so that they will be merged with implicit 1650 instantiations; otherwise we get duplicate symbol errors. 1651 For Darwin we do not want explicit instantiations to be 1652 linkonce. */ 1653 1654 void 1655 maybe_make_one_only (tree decl) 1656 { 1657 /* We used to say that this was not necessary on targets that support weak 1658 symbols, because the implicit instantiations will defer to the explicit 1659 one. However, that's not actually the case in SVR4; a strong definition 1660 after a weak one is an error. Also, not making explicit 1661 instantiations one_only means that we can end up with two copies of 1662 some template instantiations. */ 1663 if (! flag_weak) 1664 return; 1665 1666 /* We can't set DECL_COMDAT on functions, or cp_finish_file will think 1667 we can get away with not emitting them if they aren't used. We need 1668 to for variables so that cp_finish_decl will update their linkage, 1669 because their DECL_INITIAL may not have been set properly yet. */ 1670 1671 if (!TARGET_WEAK_NOT_IN_ARCHIVE_TOC 1672 || (! DECL_EXPLICIT_INSTANTIATION (decl) 1673 && ! DECL_TEMPLATE_SPECIALIZATION (decl))) 1674 { 1675 make_decl_one_only (decl, cxx_comdat_group (decl)); 1676 1677 if (TREE_CODE (decl) == VAR_DECL) 1678 { 1679 DECL_COMDAT (decl) = 1; 1680 /* Mark it needed so we don't forget to emit it. */ 1681 mark_decl_referenced (decl); 1682 } 1683 } 1684 } 1685 1686 /* Returns true iff DECL, a FUNCTION_DECL or VAR_DECL, has vague linkage. 1687 This predicate will give the right answer during parsing of the 1688 function, which other tests may not. */ 1689 1690 bool 1691 vague_linkage_p (tree decl) 1692 { 1693 /* Unfortunately, import_export_decl has not always been called 1694 before the function is processed, so we cannot simply check 1695 DECL_COMDAT. */ 1696 return (DECL_COMDAT (decl) 1697 || (((TREE_CODE (decl) == FUNCTION_DECL 1698 && DECL_DECLARED_INLINE_P (decl)) 1699 || (DECL_LANG_SPECIFIC (decl) 1700 && DECL_TEMPLATE_INSTANTIATION (decl))) 1701 && TREE_PUBLIC (decl))); 1702 } 1703 1704 /* Determine whether or not we want to specifically import or export CTYPE, 1705 using various heuristics. */ 1706 1707 static void 1708 import_export_class (tree ctype) 1709 { 1710 /* -1 for imported, 1 for exported. */ 1711 int import_export = 0; 1712 1713 /* It only makes sense to call this function at EOF. The reason is 1714 that this function looks at whether or not the first non-inline 1715 non-abstract virtual member function has been defined in this 1716 translation unit. But, we can't possibly know that until we've 1717 seen the entire translation unit. */ 1718 gcc_assert (at_eof); 1719 1720 if (CLASSTYPE_INTERFACE_KNOWN (ctype)) 1721 return; 1722 1723 /* If MULTIPLE_SYMBOL_SPACES is set and we saw a #pragma interface, 1724 we will have CLASSTYPE_INTERFACE_ONLY set but not 1725 CLASSTYPE_INTERFACE_KNOWN. In that case, we don't want to use this 1726 heuristic because someone will supply a #pragma implementation 1727 elsewhere, and deducing it here would produce a conflict. */ 1728 if (CLASSTYPE_INTERFACE_ONLY (ctype)) 1729 return; 1730 1731 if (lookup_attribute ("dllimport", TYPE_ATTRIBUTES (ctype))) 1732 import_export = -1; 1733 else if (lookup_attribute ("dllexport", TYPE_ATTRIBUTES (ctype))) 1734 import_export = 1; 1735 else if (CLASSTYPE_IMPLICIT_INSTANTIATION (ctype) 1736 && !flag_implicit_templates) 1737 /* For a template class, without -fimplicit-templates, check the 1738 repository. If the virtual table is assigned to this 1739 translation unit, then export the class; otherwise, import 1740 it. */ 1741 import_export = repo_export_class_p (ctype) ? 1 : -1; 1742 else if (TYPE_POLYMORPHIC_P (ctype)) 1743 { 1744 /* The ABI specifies that the virtual table and associated 1745 information are emitted with the key method, if any. */ 1746 tree method = CLASSTYPE_KEY_METHOD (ctype); 1747 /* If weak symbol support is not available, then we must be 1748 careful not to emit the vtable when the key function is 1749 inline. An inline function can be defined in multiple 1750 translation units. If we were to emit the vtable in each 1751 translation unit containing a definition, we would get 1752 multiple definition errors at link-time. */ 1753 if (method && (flag_weak || ! DECL_DECLARED_INLINE_P (method))) 1754 import_export = (DECL_REALLY_EXTERN (method) ? -1 : 1); 1755 } 1756 1757 /* When MULTIPLE_SYMBOL_SPACES is set, we cannot count on seeing 1758 a definition anywhere else. */ 1759 if (MULTIPLE_SYMBOL_SPACES && import_export == -1) 1760 import_export = 0; 1761 1762 /* Allow back ends the chance to overrule the decision. */ 1763 if (targetm.cxx.import_export_class) 1764 import_export = targetm.cxx.import_export_class (ctype, import_export); 1765 1766 if (import_export) 1767 { 1768 SET_CLASSTYPE_INTERFACE_KNOWN (ctype); 1769 CLASSTYPE_INTERFACE_ONLY (ctype) = (import_export < 0); 1770 } 1771 } 1772 1773 /* Return true if VAR has already been provided to the back end; in that 1774 case VAR should not be modified further by the front end. */ 1775 static bool 1776 var_finalized_p (tree var) 1777 { 1778 return varpool_node (var)->finalized; 1779 } 1780 1781 /* DECL is a VAR_DECL or FUNCTION_DECL which, for whatever reason, 1782 must be emitted in this translation unit. Mark it as such. */ 1783 1784 void 1785 mark_needed (tree decl) 1786 { 1787 /* It's possible that we no longer need to set 1788 TREE_SYMBOL_REFERENCED here directly, but doing so is 1789 harmless. */ 1790 TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)) = 1; 1791 mark_decl_referenced (decl); 1792 } 1793 1794 /* DECL is either a FUNCTION_DECL or a VAR_DECL. This function 1795 returns true if a definition of this entity should be provided in 1796 this object file. Callers use this function to determine whether 1797 or not to let the back end know that a definition of DECL is 1798 available in this translation unit. */ 1799 1800 bool 1801 decl_needed_p (tree decl) 1802 { 1803 gcc_assert (TREE_CODE (decl) == VAR_DECL 1804 || TREE_CODE (decl) == FUNCTION_DECL); 1805 /* This function should only be called at the end of the translation 1806 unit. We cannot be sure of whether or not something will be 1807 COMDAT until that point. */ 1808 gcc_assert (at_eof); 1809 1810 /* All entities with external linkage that are not COMDAT should be 1811 emitted; they may be referred to from other object files. */ 1812 if (TREE_PUBLIC (decl) && !DECL_COMDAT (decl)) 1813 return true; 1814 /* If this entity was used, let the back end see it; it will decide 1815 whether or not to emit it into the object file. */ 1816 if (TREE_USED (decl) 1817 || (DECL_ASSEMBLER_NAME_SET_P (decl) 1818 && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)))) 1819 return true; 1820 /* Functions marked "dllexport" must be emitted so that they are 1821 visible to other DLLs. */ 1822 if (flag_keep_inline_dllexport 1823 && lookup_attribute ("dllexport", DECL_ATTRIBUTES (decl))) 1824 return true; 1825 /* Otherwise, DECL does not need to be emitted -- yet. A subsequent 1826 reference to DECL might cause it to be emitted later. */ 1827 return false; 1828 } 1829 1830 /* If necessary, write out the vtables for the dynamic class CTYPE. 1831 Returns true if any vtables were emitted. */ 1832 1833 static bool 1834 maybe_emit_vtables (tree ctype) 1835 { 1836 tree vtbl; 1837 tree primary_vtbl; 1838 int needed = 0; 1839 struct varpool_node *current = NULL, *last = NULL, *first = NULL; 1840 1841 /* If the vtables for this class have already been emitted there is 1842 nothing more to do. */ 1843 primary_vtbl = CLASSTYPE_VTABLES (ctype); 1844 if (var_finalized_p (primary_vtbl)) 1845 return false; 1846 /* Ignore dummy vtables made by get_vtable_decl. */ 1847 if (TREE_TYPE (primary_vtbl) == void_type_node) 1848 return false; 1849 1850 /* On some targets, we cannot determine the key method until the end 1851 of the translation unit -- which is when this function is 1852 called. */ 1853 if (!targetm.cxx.key_method_may_be_inline ()) 1854 determine_key_method (ctype); 1855 1856 /* See if any of the vtables are needed. */ 1857 for (vtbl = CLASSTYPE_VTABLES (ctype); vtbl; vtbl = DECL_CHAIN (vtbl)) 1858 { 1859 import_export_decl (vtbl); 1860 if (DECL_NOT_REALLY_EXTERN (vtbl) && decl_needed_p (vtbl)) 1861 needed = 1; 1862 } 1863 if (!needed) 1864 { 1865 /* If the references to this class' vtables are optimized away, 1866 still emit the appropriate debugging information. See 1867 dfs_debug_mark. */ 1868 if (DECL_COMDAT (primary_vtbl) 1869 && CLASSTYPE_DEBUG_REQUESTED (ctype)) 1870 note_debug_info_needed (ctype); 1871 return false; 1872 } 1873 1874 /* The ABI requires that we emit all of the vtables if we emit any 1875 of them. */ 1876 for (vtbl = CLASSTYPE_VTABLES (ctype); vtbl; vtbl = DECL_CHAIN (vtbl)) 1877 { 1878 /* Mark entities references from the virtual table as used. */ 1879 mark_vtable_entries (vtbl); 1880 1881 if (TREE_TYPE (DECL_INITIAL (vtbl)) == 0) 1882 { 1883 VEC(tree,gc)* cleanups = NULL; 1884 tree expr = store_init_value (vtbl, DECL_INITIAL (vtbl), &cleanups, 1885 LOOKUP_NORMAL); 1886 1887 /* It had better be all done at compile-time. */ 1888 gcc_assert (!expr && !cleanups); 1889 } 1890 1891 /* Write it out. */ 1892 DECL_EXTERNAL (vtbl) = 0; 1893 rest_of_decl_compilation (vtbl, 1, 1); 1894 1895 /* Because we're only doing syntax-checking, we'll never end up 1896 actually marking the variable as written. */ 1897 if (flag_syntax_only) 1898 TREE_ASM_WRITTEN (vtbl) = 1; 1899 else if (DECL_COMDAT (vtbl)) 1900 { 1901 current = varpool_node (vtbl); 1902 if (last) 1903 last->same_comdat_group = current; 1904 last = current; 1905 if (!first) 1906 first = current; 1907 } 1908 } 1909 1910 if (first != last) 1911 last->same_comdat_group = first; 1912 1913 /* Since we're writing out the vtable here, also write the debug 1914 info. */ 1915 note_debug_info_needed (ctype); 1916 1917 return true; 1918 } 1919 1920 /* A special return value from type_visibility meaning internal 1921 linkage. */ 1922 1923 enum { VISIBILITY_ANON = VISIBILITY_INTERNAL+1 }; 1924 1925 /* walk_tree helper function for type_visibility. */ 1926 1927 static tree 1928 min_vis_r (tree *tp, int *walk_subtrees, void *data) 1929 { 1930 int *vis_p = (int *)data; 1931 if (! TYPE_P (*tp)) 1932 { 1933 *walk_subtrees = 0; 1934 } 1935 else if (CLASS_TYPE_P (*tp)) 1936 { 1937 if (!TREE_PUBLIC (TYPE_MAIN_DECL (*tp))) 1938 { 1939 *vis_p = VISIBILITY_ANON; 1940 return *tp; 1941 } 1942 else if (CLASSTYPE_VISIBILITY (*tp) > *vis_p) 1943 *vis_p = CLASSTYPE_VISIBILITY (*tp); 1944 } 1945 return NULL; 1946 } 1947 1948 /* Returns the visibility of TYPE, which is the minimum visibility of its 1949 component types. */ 1950 1951 static int 1952 type_visibility (tree type) 1953 { 1954 int vis = VISIBILITY_DEFAULT; 1955 cp_walk_tree_without_duplicates (&type, min_vis_r, &vis); 1956 return vis; 1957 } 1958 1959 /* Limit the visibility of DECL to VISIBILITY, if not explicitly 1960 specified (or if VISIBILITY is static). If TMPL is true, this 1961 constraint is for a template argument, and takes precedence 1962 over explicitly-specified visibility on the template. */ 1963 1964 static void 1965 constrain_visibility (tree decl, int visibility, bool tmpl) 1966 { 1967 if (visibility == VISIBILITY_ANON) 1968 { 1969 /* extern "C" declarations aren't affected by the anonymous 1970 namespace. */ 1971 if (!DECL_EXTERN_C_P (decl)) 1972 { 1973 TREE_PUBLIC (decl) = 0; 1974 DECL_WEAK (decl) = 0; 1975 DECL_COMMON (decl) = 0; 1976 DECL_COMDAT_GROUP (decl) = NULL_TREE; 1977 DECL_INTERFACE_KNOWN (decl) = 1; 1978 if (DECL_LANG_SPECIFIC (decl)) 1979 DECL_NOT_REALLY_EXTERN (decl) = 1; 1980 } 1981 } 1982 else if (visibility > DECL_VISIBILITY (decl) 1983 && (tmpl || !DECL_VISIBILITY_SPECIFIED (decl))) 1984 { 1985 DECL_VISIBILITY (decl) = (enum symbol_visibility) visibility; 1986 /* This visibility was not specified. */ 1987 DECL_VISIBILITY_SPECIFIED (decl) = false; 1988 } 1989 } 1990 1991 /* Constrain the visibility of DECL based on the visibility of its template 1992 arguments. */ 1993 1994 static void 1995 constrain_visibility_for_template (tree decl, tree targs) 1996 { 1997 /* If this is a template instantiation, check the innermost 1998 template args for visibility constraints. The outer template 1999 args are covered by the class check. */ 2000 tree args = INNERMOST_TEMPLATE_ARGS (targs); 2001 int i; 2002 for (i = TREE_VEC_LENGTH (args); i > 0; --i) 2003 { 2004 int vis = 0; 2005 2006 tree arg = TREE_VEC_ELT (args, i-1); 2007 if (TYPE_P (arg)) 2008 vis = type_visibility (arg); 2009 else if (TREE_TYPE (arg) && POINTER_TYPE_P (TREE_TYPE (arg))) 2010 { 2011 STRIP_NOPS (arg); 2012 if (TREE_CODE (arg) == ADDR_EXPR) 2013 arg = TREE_OPERAND (arg, 0); 2014 if (TREE_CODE (arg) == VAR_DECL 2015 || TREE_CODE (arg) == FUNCTION_DECL) 2016 { 2017 if (! TREE_PUBLIC (arg)) 2018 vis = VISIBILITY_ANON; 2019 else 2020 vis = DECL_VISIBILITY (arg); 2021 } 2022 } 2023 if (vis) 2024 constrain_visibility (decl, vis, true); 2025 } 2026 } 2027 2028 /* Like c_determine_visibility, but with additional C++-specific 2029 behavior. 2030 2031 Function-scope entities can rely on the function's visibility because 2032 it is set in start_preparsed_function. 2033 2034 Class-scope entities cannot rely on the class's visibility until the end 2035 of the enclosing class definition. 2036 2037 Note that because namespaces have multiple independent definitions, 2038 namespace visibility is handled elsewhere using the #pragma visibility 2039 machinery rather than by decorating the namespace declaration. 2040 2041 The goal is for constraints from the type to give a diagnostic, and 2042 other constraints to be applied silently. */ 2043 2044 void 2045 determine_visibility (tree decl) 2046 { 2047 tree class_type = NULL_TREE; 2048 bool use_template; 2049 bool orig_visibility_specified; 2050 enum symbol_visibility orig_visibility; 2051 2052 /* Remember that all decls get VISIBILITY_DEFAULT when built. */ 2053 2054 /* Only relevant for names with external linkage. */ 2055 if (!TREE_PUBLIC (decl)) 2056 return; 2057 2058 /* Cloned constructors and destructors get the same visibility as 2059 the underlying function. That should be set up in 2060 maybe_clone_body. */ 2061 gcc_assert (!DECL_CLONED_FUNCTION_P (decl)); 2062 2063 orig_visibility_specified = DECL_VISIBILITY_SPECIFIED (decl); 2064 orig_visibility = DECL_VISIBILITY (decl); 2065 2066 if (TREE_CODE (decl) == TYPE_DECL) 2067 { 2068 if (CLASS_TYPE_P (TREE_TYPE (decl))) 2069 use_template = CLASSTYPE_USE_TEMPLATE (TREE_TYPE (decl)); 2070 else if (TYPE_TEMPLATE_INFO (TREE_TYPE (decl))) 2071 use_template = 1; 2072 else 2073 use_template = 0; 2074 } 2075 else if (DECL_LANG_SPECIFIC (decl)) 2076 use_template = DECL_USE_TEMPLATE (decl); 2077 else 2078 use_template = 0; 2079 2080 /* If DECL is a member of a class, visibility specifiers on the 2081 class can influence the visibility of the DECL. */ 2082 if (DECL_CLASS_SCOPE_P (decl)) 2083 class_type = DECL_CONTEXT (decl); 2084 else 2085 { 2086 /* Not a class member. */ 2087 2088 /* Virtual tables have DECL_CONTEXT set to their associated class, 2089 so they are automatically handled above. */ 2090 gcc_assert (TREE_CODE (decl) != VAR_DECL 2091 || !DECL_VTABLE_OR_VTT_P (decl)); 2092 2093 if (DECL_FUNCTION_SCOPE_P (decl) && ! DECL_VISIBILITY_SPECIFIED (decl)) 2094 { 2095 /* Local statics and classes get the visibility of their 2096 containing function by default, except that 2097 -fvisibility-inlines-hidden doesn't affect them. */ 2098 tree fn = DECL_CONTEXT (decl); 2099 if (DECL_VISIBILITY_SPECIFIED (fn)) 2100 { 2101 DECL_VISIBILITY (decl) = DECL_VISIBILITY (fn); 2102 DECL_VISIBILITY_SPECIFIED (decl) = 2103 DECL_VISIBILITY_SPECIFIED (fn); 2104 } 2105 else 2106 { 2107 if (DECL_CLASS_SCOPE_P (fn)) 2108 determine_visibility_from_class (decl, DECL_CONTEXT (fn)); 2109 else if (determine_hidden_inline (fn)) 2110 { 2111 DECL_VISIBILITY (decl) = default_visibility; 2112 DECL_VISIBILITY_SPECIFIED (decl) = 2113 visibility_options.inpragma; 2114 } 2115 else 2116 { 2117 DECL_VISIBILITY (decl) = DECL_VISIBILITY (fn); 2118 DECL_VISIBILITY_SPECIFIED (decl) = 2119 DECL_VISIBILITY_SPECIFIED (fn); 2120 } 2121 } 2122 2123 /* Local classes in templates have CLASSTYPE_USE_TEMPLATE set, 2124 but have no TEMPLATE_INFO, so don't try to check it. */ 2125 use_template = 0; 2126 } 2127 else if (TREE_CODE (decl) == VAR_DECL && DECL_TINFO_P (decl) 2128 && flag_visibility_ms_compat) 2129 { 2130 /* Under -fvisibility-ms-compat, types are visible by default, 2131 even though their contents aren't. */ 2132 tree underlying_type = TREE_TYPE (DECL_NAME (decl)); 2133 int underlying_vis = type_visibility (underlying_type); 2134 if (underlying_vis == VISIBILITY_ANON 2135 || (CLASS_TYPE_P (underlying_type) 2136 && CLASSTYPE_VISIBILITY_SPECIFIED (underlying_type))) 2137 constrain_visibility (decl, underlying_vis, false); 2138 else 2139 DECL_VISIBILITY (decl) = VISIBILITY_DEFAULT; 2140 } 2141 else if (TREE_CODE (decl) == VAR_DECL && DECL_TINFO_P (decl)) 2142 { 2143 /* tinfo visibility is based on the type it's for. */ 2144 constrain_visibility 2145 (decl, type_visibility (TREE_TYPE (DECL_NAME (decl))), false); 2146 2147 /* Give the target a chance to override the visibility associated 2148 with DECL. */ 2149 if (TREE_PUBLIC (decl) 2150 && !DECL_REALLY_EXTERN (decl) 2151 && CLASS_TYPE_P (TREE_TYPE (DECL_NAME (decl))) 2152 && !CLASSTYPE_VISIBILITY_SPECIFIED (TREE_TYPE (DECL_NAME (decl)))) 2153 targetm.cxx.determine_class_data_visibility (decl); 2154 } 2155 else if (use_template) 2156 /* Template instantiations and specializations get visibility based 2157 on their template unless they override it with an attribute. */; 2158 else if (! DECL_VISIBILITY_SPECIFIED (decl)) 2159 { 2160 if (determine_hidden_inline (decl)) 2161 DECL_VISIBILITY (decl) = VISIBILITY_HIDDEN; 2162 else 2163 { 2164 /* Set default visibility to whatever the user supplied with 2165 #pragma GCC visibility or a namespace visibility attribute. */ 2166 DECL_VISIBILITY (decl) = default_visibility; 2167 DECL_VISIBILITY_SPECIFIED (decl) = visibility_options.inpragma; 2168 } 2169 } 2170 } 2171 2172 if (use_template) 2173 { 2174 /* If the specialization doesn't specify visibility, use the 2175 visibility from the template. */ 2176 tree tinfo = (TREE_CODE (decl) == TYPE_DECL 2177 ? TYPE_TEMPLATE_INFO (TREE_TYPE (decl)) 2178 : DECL_TEMPLATE_INFO (decl)); 2179 tree args = TI_ARGS (tinfo); 2180 tree attribs = (TREE_CODE (decl) == TYPE_DECL 2181 ? TYPE_ATTRIBUTES (TREE_TYPE (decl)) 2182 : DECL_ATTRIBUTES (decl)); 2183 2184 if (args != error_mark_node 2185 /* Template argument visibility outweighs #pragma or namespace 2186 visibility, but not an explicit attribute. */ 2187 && !lookup_attribute ("visibility", attribs)) 2188 { 2189 int depth = TMPL_ARGS_DEPTH (args); 2190 tree pattern = DECL_TEMPLATE_RESULT (TI_TEMPLATE (tinfo)); 2191 2192 if (!DECL_VISIBILITY_SPECIFIED (decl)) 2193 { 2194 if (!DECL_VISIBILITY_SPECIFIED (pattern) 2195 && determine_hidden_inline (decl)) 2196 DECL_VISIBILITY (decl) = VISIBILITY_HIDDEN; 2197 else 2198 { 2199 DECL_VISIBILITY (decl) = DECL_VISIBILITY (pattern); 2200 DECL_VISIBILITY_SPECIFIED (decl) 2201 = DECL_VISIBILITY_SPECIFIED (pattern); 2202 } 2203 } 2204 2205 /* FIXME should TMPL_ARGS_DEPTH really return 1 for null input? */ 2206 if (args && depth > template_class_depth (class_type)) 2207 /* Limit visibility based on its template arguments. */ 2208 constrain_visibility_for_template (decl, args); 2209 } 2210 } 2211 2212 if (class_type) 2213 determine_visibility_from_class (decl, class_type); 2214 2215 if (decl_anon_ns_mem_p (decl)) 2216 /* Names in an anonymous namespace get internal linkage. 2217 This might change once we implement export. */ 2218 constrain_visibility (decl, VISIBILITY_ANON, false); 2219 else if (TREE_CODE (decl) != TYPE_DECL) 2220 { 2221 /* Propagate anonymity from type to decl. */ 2222 int tvis = type_visibility (TREE_TYPE (decl)); 2223 if (tvis == VISIBILITY_ANON 2224 || ! DECL_VISIBILITY_SPECIFIED (decl)) 2225 constrain_visibility (decl, tvis, false); 2226 } 2227 else if (no_linkage_check (TREE_TYPE (decl), /*relaxed_p=*/true)) 2228 /* DR 757: A type without linkage shall not be used as the type of a 2229 variable or function with linkage, unless 2230 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or 2231 o the variable or function is not used (3.2 [basic.def.odr]) or is 2232 defined in the same translation unit. 2233 2234 Since non-extern "C" decls need to be defined in the same 2235 translation unit, we can make the type internal. */ 2236 constrain_visibility (decl, VISIBILITY_ANON, false); 2237 2238 /* If visibility changed and DECL already has DECL_RTL, ensure 2239 symbol flags are updated. */ 2240 if ((DECL_VISIBILITY (decl) != orig_visibility 2241 || DECL_VISIBILITY_SPECIFIED (decl) != orig_visibility_specified) 2242 && ((TREE_CODE (decl) == VAR_DECL && TREE_STATIC (decl)) 2243 || TREE_CODE (decl) == FUNCTION_DECL) 2244 && DECL_RTL_SET_P (decl)) 2245 make_decl_rtl (decl); 2246 } 2247 2248 /* By default, static data members and function members receive 2249 the visibility of their containing class. */ 2250 2251 static void 2252 determine_visibility_from_class (tree decl, tree class_type) 2253 { 2254 if (DECL_VISIBILITY_SPECIFIED (decl)) 2255 return; 2256 2257 if (determine_hidden_inline (decl)) 2258 DECL_VISIBILITY (decl) = VISIBILITY_HIDDEN; 2259 else 2260 { 2261 /* Default to the class visibility. */ 2262 DECL_VISIBILITY (decl) = CLASSTYPE_VISIBILITY (class_type); 2263 DECL_VISIBILITY_SPECIFIED (decl) 2264 = CLASSTYPE_VISIBILITY_SPECIFIED (class_type); 2265 } 2266 2267 /* Give the target a chance to override the visibility associated 2268 with DECL. */ 2269 if (TREE_CODE (decl) == VAR_DECL 2270 && (DECL_TINFO_P (decl) 2271 || (DECL_VTABLE_OR_VTT_P (decl) 2272 /* Construction virtual tables are not exported because 2273 they cannot be referred to from other object files; 2274 their name is not standardized by the ABI. */ 2275 && !DECL_CONSTRUCTION_VTABLE_P (decl))) 2276 && TREE_PUBLIC (decl) 2277 && !DECL_REALLY_EXTERN (decl) 2278 && !CLASSTYPE_VISIBILITY_SPECIFIED (class_type)) 2279 targetm.cxx.determine_class_data_visibility (decl); 2280 } 2281 2282 /* Returns true iff DECL is an inline that should get hidden visibility 2283 because of -fvisibility-inlines-hidden. */ 2284 2285 static bool 2286 determine_hidden_inline (tree decl) 2287 { 2288 return (visibility_options.inlines_hidden 2289 /* Don't do this for inline templates; specializations might not be 2290 inline, and we don't want them to inherit the hidden 2291 visibility. We'll set it here for all inline instantiations. */ 2292 && !processing_template_decl 2293 && TREE_CODE (decl) == FUNCTION_DECL 2294 && DECL_DECLARED_INLINE_P (decl) 2295 && (! DECL_LANG_SPECIFIC (decl) 2296 || ! DECL_EXPLICIT_INSTANTIATION (decl))); 2297 } 2298 2299 /* Constrain the visibility of a class TYPE based on the visibility of its 2300 field types. Warn if any fields require lesser visibility. */ 2301 2302 void 2303 constrain_class_visibility (tree type) 2304 { 2305 tree binfo; 2306 tree t; 2307 int i; 2308 2309 int vis = type_visibility (type); 2310 2311 if (vis == VISIBILITY_ANON 2312 || DECL_IN_SYSTEM_HEADER (TYPE_MAIN_DECL (type))) 2313 return; 2314 2315 /* Don't warn about visibility if the class has explicit visibility. */ 2316 if (CLASSTYPE_VISIBILITY_SPECIFIED (type)) 2317 vis = VISIBILITY_INTERNAL; 2318 2319 for (t = TYPE_FIELDS (type); t; t = DECL_CHAIN (t)) 2320 if (TREE_CODE (t) == FIELD_DECL && TREE_TYPE (t) != error_mark_node) 2321 { 2322 tree ftype = strip_pointer_or_array_types (TREE_TYPE (t)); 2323 int subvis = type_visibility (ftype); 2324 2325 if (subvis == VISIBILITY_ANON) 2326 { 2327 if (!in_main_input_context ()) 2328 warning (0, "\ 2329 %qT has a field %qD whose type uses the anonymous namespace", 2330 type, t); 2331 } 2332 else if (MAYBE_CLASS_TYPE_P (ftype) 2333 && vis < VISIBILITY_HIDDEN 2334 && subvis >= VISIBILITY_HIDDEN) 2335 warning (OPT_Wattributes, "\ 2336 %qT declared with greater visibility than the type of its field %qD", 2337 type, t); 2338 } 2339 2340 binfo = TYPE_BINFO (type); 2341 for (i = 0; BINFO_BASE_ITERATE (binfo, i, t); ++i) 2342 { 2343 int subvis = type_visibility (TREE_TYPE (t)); 2344 2345 if (subvis == VISIBILITY_ANON) 2346 { 2347 if (!in_main_input_context()) 2348 warning (0, "\ 2349 %qT has a base %qT whose type uses the anonymous namespace", 2350 type, TREE_TYPE (t)); 2351 } 2352 else if (vis < VISIBILITY_HIDDEN 2353 && subvis >= VISIBILITY_HIDDEN) 2354 warning (OPT_Wattributes, "\ 2355 %qT declared with greater visibility than its base %qT", 2356 type, TREE_TYPE (t)); 2357 } 2358 } 2359 2360 /* DECL is a FUNCTION_DECL or VAR_DECL. If the object file linkage 2361 for DECL has not already been determined, do so now by setting 2362 DECL_EXTERNAL, DECL_COMDAT and other related flags. Until this 2363 function is called entities with vague linkage whose definitions 2364 are available must have TREE_PUBLIC set. 2365 2366 If this function decides to place DECL in COMDAT, it will set 2367 appropriate flags -- but will not clear DECL_EXTERNAL. It is up to 2368 the caller to decide whether or not to clear DECL_EXTERNAL. Some 2369 callers defer that decision until it is clear that DECL is actually 2370 required. */ 2371 2372 void 2373 import_export_decl (tree decl) 2374 { 2375 int emit_p; 2376 bool comdat_p; 2377 bool import_p; 2378 tree class_type = NULL_TREE; 2379 2380 if (DECL_INTERFACE_KNOWN (decl)) 2381 return; 2382 2383 /* We cannot determine what linkage to give to an entity with vague 2384 linkage until the end of the file. For example, a virtual table 2385 for a class will be defined if and only if the key method is 2386 defined in this translation unit. As a further example, consider 2387 that when compiling a translation unit that uses PCH file with 2388 "-frepo" it would be incorrect to make decisions about what 2389 entities to emit when building the PCH; those decisions must be 2390 delayed until the repository information has been processed. */ 2391 gcc_assert (at_eof); 2392 /* Object file linkage for explicit instantiations is handled in 2393 mark_decl_instantiated. For static variables in functions with 2394 vague linkage, maybe_commonize_var is used. 2395 2396 Therefore, the only declarations that should be provided to this 2397 function are those with external linkage that are: 2398 2399 * implicit instantiations of function templates 2400 2401 * inline function 2402 2403 * implicit instantiations of static data members of class 2404 templates 2405 2406 * virtual tables 2407 2408 * typeinfo objects 2409 2410 Furthermore, all entities that reach this point must have a 2411 definition available in this translation unit. 2412 2413 The following assertions check these conditions. */ 2414 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL 2415 || TREE_CODE (decl) == VAR_DECL); 2416 /* Any code that creates entities with TREE_PUBLIC cleared should 2417 also set DECL_INTERFACE_KNOWN. */ 2418 gcc_assert (TREE_PUBLIC (decl)); 2419 if (TREE_CODE (decl) == FUNCTION_DECL) 2420 gcc_assert (DECL_IMPLICIT_INSTANTIATION (decl) 2421 || DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (decl) 2422 || DECL_DECLARED_INLINE_P (decl)); 2423 else 2424 gcc_assert (DECL_IMPLICIT_INSTANTIATION (decl) 2425 || DECL_VTABLE_OR_VTT_P (decl) 2426 || DECL_TINFO_P (decl)); 2427 /* Check that a definition of DECL is available in this translation 2428 unit. */ 2429 gcc_assert (!DECL_REALLY_EXTERN (decl)); 2430 2431 /* Assume that DECL will not have COMDAT linkage. */ 2432 comdat_p = false; 2433 /* Assume that DECL will not be imported into this translation 2434 unit. */ 2435 import_p = false; 2436 2437 /* See if the repository tells us whether or not to emit DECL in 2438 this translation unit. */ 2439 emit_p = repo_emit_p (decl); 2440 if (emit_p == 0) 2441 import_p = true; 2442 else if (emit_p == 1) 2443 { 2444 /* The repository indicates that this entity should be defined 2445 here. Make sure the back end honors that request. */ 2446 if (TREE_CODE (decl) == VAR_DECL) 2447 mark_needed (decl); 2448 else if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (decl) 2449 || DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (decl)) 2450 { 2451 tree clone; 2452 FOR_EACH_CLONE (clone, decl) 2453 mark_needed (clone); 2454 } 2455 else 2456 mark_needed (decl); 2457 /* Output the definition as an ordinary strong definition. */ 2458 DECL_EXTERNAL (decl) = 0; 2459 DECL_INTERFACE_KNOWN (decl) = 1; 2460 return; 2461 } 2462 2463 if (import_p) 2464 /* We have already decided what to do with this DECL; there is no 2465 need to check anything further. */ 2466 ; 2467 else if (TREE_CODE (decl) == VAR_DECL && DECL_VTABLE_OR_VTT_P (decl)) 2468 { 2469 class_type = DECL_CONTEXT (decl); 2470 import_export_class (class_type); 2471 if (TYPE_FOR_JAVA (class_type)) 2472 import_p = true; 2473 else if (CLASSTYPE_INTERFACE_KNOWN (class_type) 2474 && CLASSTYPE_INTERFACE_ONLY (class_type)) 2475 import_p = true; 2476 else if ((!flag_weak || TARGET_WEAK_NOT_IN_ARCHIVE_TOC) 2477 && !CLASSTYPE_USE_TEMPLATE (class_type) 2478 && CLASSTYPE_KEY_METHOD (class_type) 2479 && !DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (class_type))) 2480 /* The ABI requires that all virtual tables be emitted with 2481 COMDAT linkage. However, on systems where COMDAT symbols 2482 don't show up in the table of contents for a static 2483 archive, or on systems without weak symbols (where we 2484 approximate COMDAT linkage by using internal linkage), the 2485 linker will report errors about undefined symbols because 2486 it will not see the virtual table definition. Therefore, 2487 in the case that we know that the virtual table will be 2488 emitted in only one translation unit, we make the virtual 2489 table an ordinary definition with external linkage. */ 2490 DECL_EXTERNAL (decl) = 0; 2491 else if (CLASSTYPE_INTERFACE_KNOWN (class_type)) 2492 { 2493 /* CLASS_TYPE is being exported from this translation unit, 2494 so DECL should be defined here. */ 2495 if (!flag_weak && CLASSTYPE_EXPLICIT_INSTANTIATION (class_type)) 2496 /* If a class is declared in a header with the "extern 2497 template" extension, then it will not be instantiated, 2498 even in translation units that would normally require 2499 it. Often such classes are explicitly instantiated in 2500 one translation unit. Therefore, the explicit 2501 instantiation must be made visible to other translation 2502 units. */ 2503 DECL_EXTERNAL (decl) = 0; 2504 else 2505 { 2506 /* The generic C++ ABI says that class data is always 2507 COMDAT, even if there is a key function. Some 2508 variants (e.g., the ARM EABI) says that class data 2509 only has COMDAT linkage if the class data might be 2510 emitted in more than one translation unit. When the 2511 key method can be inline and is inline, we still have 2512 to arrange for comdat even though 2513 class_data_always_comdat is false. */ 2514 if (!CLASSTYPE_KEY_METHOD (class_type) 2515 || DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (class_type)) 2516 || targetm.cxx.class_data_always_comdat ()) 2517 { 2518 /* The ABI requires COMDAT linkage. Normally, we 2519 only emit COMDAT things when they are needed; 2520 make sure that we realize that this entity is 2521 indeed needed. */ 2522 comdat_p = true; 2523 mark_needed (decl); 2524 } 2525 } 2526 } 2527 else if (!flag_implicit_templates 2528 && CLASSTYPE_IMPLICIT_INSTANTIATION (class_type)) 2529 import_p = true; 2530 else 2531 comdat_p = true; 2532 } 2533 else if (TREE_CODE (decl) == VAR_DECL && DECL_TINFO_P (decl)) 2534 { 2535 tree type = TREE_TYPE (DECL_NAME (decl)); 2536 if (CLASS_TYPE_P (type)) 2537 { 2538 class_type = type; 2539 import_export_class (type); 2540 if (CLASSTYPE_INTERFACE_KNOWN (type) 2541 && TYPE_POLYMORPHIC_P (type) 2542 && CLASSTYPE_INTERFACE_ONLY (type) 2543 /* If -fno-rtti was specified, then we cannot be sure 2544 that RTTI information will be emitted with the 2545 virtual table of the class, so we must emit it 2546 wherever it is used. */ 2547 && flag_rtti) 2548 import_p = true; 2549 else 2550 { 2551 if (CLASSTYPE_INTERFACE_KNOWN (type) 2552 && !CLASSTYPE_INTERFACE_ONLY (type)) 2553 { 2554 comdat_p = (targetm.cxx.class_data_always_comdat () 2555 || (CLASSTYPE_KEY_METHOD (type) 2556 && DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (type)))); 2557 mark_needed (decl); 2558 if (!flag_weak) 2559 { 2560 comdat_p = false; 2561 DECL_EXTERNAL (decl) = 0; 2562 } 2563 } 2564 else 2565 comdat_p = true; 2566 } 2567 } 2568 else 2569 comdat_p = true; 2570 } 2571 else if (DECL_TEMPLATE_INSTANTIATION (decl) 2572 || DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (decl)) 2573 { 2574 /* DECL is an implicit instantiation of a function or static 2575 data member. */ 2576 if ((flag_implicit_templates 2577 && !flag_use_repository) 2578 || (flag_implicit_inline_templates 2579 && TREE_CODE (decl) == FUNCTION_DECL 2580 && DECL_DECLARED_INLINE_P (decl))) 2581 comdat_p = true; 2582 else 2583 /* If we are not implicitly generating templates, then mark 2584 this entity as undefined in this translation unit. */ 2585 import_p = true; 2586 } 2587 else if (DECL_FUNCTION_MEMBER_P (decl)) 2588 { 2589 if (!DECL_DECLARED_INLINE_P (decl)) 2590 { 2591 tree ctype = DECL_CONTEXT (decl); 2592 import_export_class (ctype); 2593 if (CLASSTYPE_INTERFACE_KNOWN (ctype)) 2594 { 2595 DECL_NOT_REALLY_EXTERN (decl) 2596 = ! (CLASSTYPE_INTERFACE_ONLY (ctype) 2597 || (DECL_DECLARED_INLINE_P (decl) 2598 && ! flag_implement_inlines 2599 && !DECL_VINDEX (decl))); 2600 2601 if (!DECL_NOT_REALLY_EXTERN (decl)) 2602 DECL_EXTERNAL (decl) = 1; 2603 2604 /* Always make artificials weak. */ 2605 if (DECL_ARTIFICIAL (decl) && flag_weak) 2606 comdat_p = true; 2607 else 2608 maybe_make_one_only (decl); 2609 } 2610 } 2611 else 2612 comdat_p = true; 2613 } 2614 else 2615 comdat_p = true; 2616 2617 if (import_p) 2618 { 2619 /* If we are importing DECL into this translation unit, mark is 2620 an undefined here. */ 2621 DECL_EXTERNAL (decl) = 1; 2622 DECL_NOT_REALLY_EXTERN (decl) = 0; 2623 } 2624 else if (comdat_p) 2625 { 2626 /* If we decided to put DECL in COMDAT, mark it accordingly at 2627 this point. */ 2628 comdat_linkage (decl); 2629 } 2630 2631 DECL_INTERFACE_KNOWN (decl) = 1; 2632 } 2633 2634 /* Return an expression that performs the destruction of DECL, which 2635 must be a VAR_DECL whose type has a non-trivial destructor, or is 2636 an array whose (innermost) elements have a non-trivial destructor. */ 2637 2638 tree 2639 build_cleanup (tree decl) 2640 { 2641 tree temp; 2642 tree type = TREE_TYPE (decl); 2643 2644 /* This function should only be called for declarations that really 2645 require cleanups. */ 2646 gcc_assert (!TYPE_HAS_TRIVIAL_DESTRUCTOR (type)); 2647 2648 /* Treat all objects with destructors as used; the destructor may do 2649 something substantive. */ 2650 mark_used (decl); 2651 2652 if (TREE_CODE (type) == ARRAY_TYPE) 2653 temp = decl; 2654 else 2655 temp = build_address (decl); 2656 temp = build_delete (TREE_TYPE (temp), temp, 2657 sfk_complete_destructor, 2658 LOOKUP_NORMAL|LOOKUP_NONVIRTUAL|LOOKUP_DESTRUCTOR, 0, 2659 tf_warning_or_error); 2660 return temp; 2661 } 2662 2663 /* Returns the initialization guard variable for the variable DECL, 2664 which has static storage duration. */ 2665 2666 tree 2667 get_guard (tree decl) 2668 { 2669 tree sname; 2670 tree guard; 2671 2672 sname = mangle_guard_variable (decl); 2673 guard = IDENTIFIER_GLOBAL_VALUE (sname); 2674 if (! guard) 2675 { 2676 tree guard_type; 2677 2678 /* We use a type that is big enough to contain a mutex as well 2679 as an integer counter. */ 2680 guard_type = targetm.cxx.guard_type (); 2681 guard = build_decl (DECL_SOURCE_LOCATION (decl), 2682 VAR_DECL, sname, guard_type); 2683 2684 /* The guard should have the same linkage as what it guards. */ 2685 TREE_PUBLIC (guard) = TREE_PUBLIC (decl); 2686 TREE_STATIC (guard) = TREE_STATIC (decl); 2687 DECL_COMMON (guard) = DECL_COMMON (decl); 2688 DECL_COMDAT (guard) = DECL_COMDAT (decl); 2689 if (DECL_ONE_ONLY (decl)) 2690 make_decl_one_only (guard, cxx_comdat_group (guard)); 2691 if (TREE_PUBLIC (decl)) 2692 DECL_WEAK (guard) = DECL_WEAK (decl); 2693 DECL_VISIBILITY (guard) = DECL_VISIBILITY (decl); 2694 DECL_VISIBILITY_SPECIFIED (guard) = DECL_VISIBILITY_SPECIFIED (decl); 2695 2696 DECL_ARTIFICIAL (guard) = 1; 2697 DECL_IGNORED_P (guard) = 1; 2698 TREE_USED (guard) = 1; 2699 pushdecl_top_level_and_finish (guard, NULL_TREE); 2700 } 2701 return guard; 2702 } 2703 2704 /* Return those bits of the GUARD variable that should be set when the 2705 guarded entity is actually initialized. */ 2706 2707 static tree 2708 get_guard_bits (tree guard) 2709 { 2710 if (!targetm.cxx.guard_mask_bit ()) 2711 { 2712 /* We only set the first byte of the guard, in order to leave room 2713 for a mutex in the high-order bits. */ 2714 guard = build1 (ADDR_EXPR, 2715 build_pointer_type (TREE_TYPE (guard)), 2716 guard); 2717 guard = build1 (NOP_EXPR, 2718 build_pointer_type (char_type_node), 2719 guard); 2720 guard = build1 (INDIRECT_REF, char_type_node, guard); 2721 } 2722 2723 return guard; 2724 } 2725 2726 /* Return an expression which determines whether or not the GUARD 2727 variable has already been initialized. */ 2728 2729 tree 2730 get_guard_cond (tree guard) 2731 { 2732 tree guard_value; 2733 2734 /* Check to see if the GUARD is zero. */ 2735 guard = get_guard_bits (guard); 2736 2737 /* Mask off all but the low bit. */ 2738 if (targetm.cxx.guard_mask_bit ()) 2739 { 2740 guard_value = integer_one_node; 2741 if (!same_type_p (TREE_TYPE (guard_value), TREE_TYPE (guard))) 2742 guard_value = convert (TREE_TYPE (guard), guard_value); 2743 guard = cp_build_binary_op (input_location, 2744 BIT_AND_EXPR, guard, guard_value, 2745 tf_warning_or_error); 2746 } 2747 2748 guard_value = integer_zero_node; 2749 if (!same_type_p (TREE_TYPE (guard_value), TREE_TYPE (guard))) 2750 guard_value = convert (TREE_TYPE (guard), guard_value); 2751 return cp_build_binary_op (input_location, 2752 EQ_EXPR, guard, guard_value, 2753 tf_warning_or_error); 2754 } 2755 2756 /* Return an expression which sets the GUARD variable, indicating that 2757 the variable being guarded has been initialized. */ 2758 2759 tree 2760 set_guard (tree guard) 2761 { 2762 tree guard_init; 2763 2764 /* Set the GUARD to one. */ 2765 guard = get_guard_bits (guard); 2766 guard_init = integer_one_node; 2767 if (!same_type_p (TREE_TYPE (guard_init), TREE_TYPE (guard))) 2768 guard_init = convert (TREE_TYPE (guard), guard_init); 2769 return cp_build_modify_expr (guard, NOP_EXPR, guard_init, 2770 tf_warning_or_error); 2771 } 2772 2773 /* Start the process of running a particular set of global constructors 2774 or destructors. Subroutine of do_[cd]tors. */ 2775 2776 static tree 2777 start_objects (int method_type, int initp) 2778 { 2779 tree body; 2780 tree fndecl; 2781 char type[14]; 2782 2783 /* Make ctor or dtor function. METHOD_TYPE may be 'I' or 'D'. */ 2784 2785 if (initp != DEFAULT_INIT_PRIORITY) 2786 { 2787 char joiner; 2788 2789 #ifdef JOINER 2790 joiner = JOINER; 2791 #else 2792 joiner = '_'; 2793 #endif 2794 2795 sprintf (type, "sub_%c%c%.5u", method_type, joiner, initp); 2796 } 2797 else 2798 sprintf (type, "sub_%c", method_type); 2799 2800 fndecl = build_lang_decl (FUNCTION_DECL, 2801 get_file_function_name (type), 2802 build_function_type_list (void_type_node, 2803 NULL_TREE)); 2804 start_preparsed_function (fndecl, /*attrs=*/NULL_TREE, SF_PRE_PARSED); 2805 2806 TREE_PUBLIC (current_function_decl) = 0; 2807 2808 /* Mark as artificial because it's not explicitly in the user's 2809 source code. */ 2810 DECL_ARTIFICIAL (current_function_decl) = 1; 2811 2812 /* Mark this declaration as used to avoid spurious warnings. */ 2813 TREE_USED (current_function_decl) = 1; 2814 2815 /* Mark this function as a global constructor or destructor. */ 2816 if (method_type == 'I') 2817 DECL_GLOBAL_CTOR_P (current_function_decl) = 1; 2818 else 2819 DECL_GLOBAL_DTOR_P (current_function_decl) = 1; 2820 2821 body = begin_compound_stmt (BCS_FN_BODY); 2822 2823 return body; 2824 } 2825 2826 /* Finish the process of running a particular set of global constructors 2827 or destructors. Subroutine of do_[cd]tors. */ 2828 2829 static void 2830 finish_objects (int method_type, int initp, tree body) 2831 { 2832 tree fn; 2833 2834 /* Finish up. */ 2835 finish_compound_stmt (body); 2836 fn = finish_function (0); 2837 2838 if (method_type == 'I') 2839 { 2840 DECL_STATIC_CONSTRUCTOR (fn) = 1; 2841 decl_init_priority_insert (fn, initp); 2842 } 2843 else 2844 { 2845 DECL_STATIC_DESTRUCTOR (fn) = 1; 2846 decl_fini_priority_insert (fn, initp); 2847 } 2848 2849 expand_or_defer_fn (fn); 2850 } 2851 2852 /* The names of the parameters to the function created to handle 2853 initializations and destructions for objects with static storage 2854 duration. */ 2855 #define INITIALIZE_P_IDENTIFIER "__initialize_p" 2856 #define PRIORITY_IDENTIFIER "__priority" 2857 2858 /* The name of the function we create to handle initializations and 2859 destructions for objects with static storage duration. */ 2860 #define SSDF_IDENTIFIER "__static_initialization_and_destruction" 2861 2862 /* The declaration for the __INITIALIZE_P argument. */ 2863 static GTY(()) tree initialize_p_decl; 2864 2865 /* The declaration for the __PRIORITY argument. */ 2866 static GTY(()) tree priority_decl; 2867 2868 /* The declaration for the static storage duration function. */ 2869 static GTY(()) tree ssdf_decl; 2870 2871 /* All the static storage duration functions created in this 2872 translation unit. */ 2873 static GTY(()) VEC(tree,gc) *ssdf_decls; 2874 2875 /* A map from priority levels to information about that priority 2876 level. There may be many such levels, so efficient lookup is 2877 important. */ 2878 static splay_tree priority_info_map; 2879 2880 /* Begins the generation of the function that will handle all 2881 initialization and destruction of objects with static storage 2882 duration. The function generated takes two parameters of type 2883 `int': __INITIALIZE_P and __PRIORITY. If __INITIALIZE_P is 2884 nonzero, it performs initializations. Otherwise, it performs 2885 destructions. It only performs those initializations or 2886 destructions with the indicated __PRIORITY. The generated function 2887 returns no value. 2888 2889 It is assumed that this function will only be called once per 2890 translation unit. */ 2891 2892 static tree 2893 start_static_storage_duration_function (unsigned count) 2894 { 2895 tree type; 2896 tree body; 2897 char id[sizeof (SSDF_IDENTIFIER) + 1 /* '\0' */ + 32]; 2898 2899 /* Create the identifier for this function. It will be of the form 2900 SSDF_IDENTIFIER_<number>. */ 2901 sprintf (id, "%s_%u", SSDF_IDENTIFIER, count); 2902 2903 type = build_function_type_list (void_type_node, 2904 integer_type_node, integer_type_node, 2905 NULL_TREE); 2906 2907 /* Create the FUNCTION_DECL itself. */ 2908 ssdf_decl = build_lang_decl (FUNCTION_DECL, 2909 get_identifier (id), 2910 type); 2911 TREE_PUBLIC (ssdf_decl) = 0; 2912 DECL_ARTIFICIAL (ssdf_decl) = 1; 2913 2914 /* Put this function in the list of functions to be called from the 2915 static constructors and destructors. */ 2916 if (!ssdf_decls) 2917 { 2918 ssdf_decls = VEC_alloc (tree, gc, 32); 2919 2920 /* Take this opportunity to initialize the map from priority 2921 numbers to information about that priority level. */ 2922 priority_info_map = splay_tree_new (splay_tree_compare_ints, 2923 /*delete_key_fn=*/0, 2924 /*delete_value_fn=*/ 2925 (splay_tree_delete_value_fn) &free); 2926 2927 /* We always need to generate functions for the 2928 DEFAULT_INIT_PRIORITY so enter it now. That way when we walk 2929 priorities later, we'll be sure to find the 2930 DEFAULT_INIT_PRIORITY. */ 2931 get_priority_info (DEFAULT_INIT_PRIORITY); 2932 } 2933 2934 VEC_safe_push (tree, gc, ssdf_decls, ssdf_decl); 2935 2936 /* Create the argument list. */ 2937 initialize_p_decl = cp_build_parm_decl 2938 (get_identifier (INITIALIZE_P_IDENTIFIER), integer_type_node); 2939 DECL_CONTEXT (initialize_p_decl) = ssdf_decl; 2940 TREE_USED (initialize_p_decl) = 1; 2941 priority_decl = cp_build_parm_decl 2942 (get_identifier (PRIORITY_IDENTIFIER), integer_type_node); 2943 DECL_CONTEXT (priority_decl) = ssdf_decl; 2944 TREE_USED (priority_decl) = 1; 2945 2946 DECL_CHAIN (initialize_p_decl) = priority_decl; 2947 DECL_ARGUMENTS (ssdf_decl) = initialize_p_decl; 2948 2949 /* Put the function in the global scope. */ 2950 pushdecl (ssdf_decl); 2951 2952 /* Start the function itself. This is equivalent to declaring the 2953 function as: 2954 2955 static void __ssdf (int __initialize_p, init __priority_p); 2956 2957 It is static because we only need to call this function from the 2958 various constructor and destructor functions for this module. */ 2959 start_preparsed_function (ssdf_decl, 2960 /*attrs=*/NULL_TREE, 2961 SF_PRE_PARSED); 2962 2963 /* Set up the scope of the outermost block in the function. */ 2964 body = begin_compound_stmt (BCS_FN_BODY); 2965 2966 return body; 2967 } 2968 2969 /* Finish the generation of the function which performs initialization 2970 and destruction of objects with static storage duration. After 2971 this point, no more such objects can be created. */ 2972 2973 static void 2974 finish_static_storage_duration_function (tree body) 2975 { 2976 /* Close out the function. */ 2977 finish_compound_stmt (body); 2978 expand_or_defer_fn (finish_function (0)); 2979 } 2980 2981 /* Return the information about the indicated PRIORITY level. If no 2982 code to handle this level has yet been generated, generate the 2983 appropriate prologue. */ 2984 2985 static priority_info 2986 get_priority_info (int priority) 2987 { 2988 priority_info pi; 2989 splay_tree_node n; 2990 2991 n = splay_tree_lookup (priority_info_map, 2992 (splay_tree_key) priority); 2993 if (!n) 2994 { 2995 /* Create a new priority information structure, and insert it 2996 into the map. */ 2997 pi = XNEW (struct priority_info_s); 2998 pi->initializations_p = 0; 2999 pi->destructions_p = 0; 3000 splay_tree_insert (priority_info_map, 3001 (splay_tree_key) priority, 3002 (splay_tree_value) pi); 3003 } 3004 else 3005 pi = (priority_info) n->value; 3006 3007 return pi; 3008 } 3009 3010 /* The effective initialization priority of a DECL. */ 3011 3012 #define DECL_EFFECTIVE_INIT_PRIORITY(decl) \ 3013 ((!DECL_HAS_INIT_PRIORITY_P (decl) || DECL_INIT_PRIORITY (decl) == 0) \ 3014 ? DEFAULT_INIT_PRIORITY : DECL_INIT_PRIORITY (decl)) 3015 3016 /* Whether a DECL needs a guard to protect it against multiple 3017 initialization. */ 3018 3019 #define NEEDS_GUARD_P(decl) (TREE_PUBLIC (decl) && (DECL_COMMON (decl) \ 3020 || DECL_ONE_ONLY (decl) \ 3021 || DECL_WEAK (decl))) 3022 3023 /* Called from one_static_initialization_or_destruction(), 3024 via walk_tree. 3025 Walks the initializer list of a global variable and looks for 3026 temporary variables (DECL_NAME() == NULL and DECL_ARTIFICIAL != 0) 3027 and that have their DECL_CONTEXT() == NULL. 3028 For each such temporary variable, set their DECL_CONTEXT() to 3029 the current function. This is necessary because otherwise 3030 some optimizers (enabled by -O2 -fprofile-arcs) might crash 3031 when trying to refer to a temporary variable that does not have 3032 it's DECL_CONTECT() properly set. */ 3033 static tree 3034 fix_temporary_vars_context_r (tree *node, 3035 int *unused ATTRIBUTE_UNUSED, 3036 void *unused1 ATTRIBUTE_UNUSED) 3037 { 3038 gcc_assert (current_function_decl); 3039 3040 if (TREE_CODE (*node) == BIND_EXPR) 3041 { 3042 tree var; 3043 3044 for (var = BIND_EXPR_VARS (*node); var; var = DECL_CHAIN (var)) 3045 if (TREE_CODE (var) == VAR_DECL 3046 && !DECL_NAME (var) 3047 && DECL_ARTIFICIAL (var) 3048 && !DECL_CONTEXT (var)) 3049 DECL_CONTEXT (var) = current_function_decl; 3050 } 3051 3052 return NULL_TREE; 3053 } 3054 3055 /* Set up to handle the initialization or destruction of DECL. If 3056 INITP is nonzero, we are initializing the variable. Otherwise, we 3057 are destroying it. */ 3058 3059 static void 3060 one_static_initialization_or_destruction (tree decl, tree init, bool initp) 3061 { 3062 tree guard_if_stmt = NULL_TREE; 3063 tree guard; 3064 3065 /* If we are supposed to destruct and there's a trivial destructor, 3066 nothing has to be done. */ 3067 if (!initp 3068 && TYPE_HAS_TRIVIAL_DESTRUCTOR (TREE_TYPE (decl))) 3069 return; 3070 3071 /* Trick the compiler into thinking we are at the file and line 3072 where DECL was declared so that error-messages make sense, and so 3073 that the debugger will show somewhat sensible file and line 3074 information. */ 3075 input_location = DECL_SOURCE_LOCATION (decl); 3076 3077 /* Make sure temporary variables in the initialiser all have 3078 their DECL_CONTEXT() set to a value different from NULL_TREE. 3079 This can happen when global variables initialisers are built. 3080 In that case, the DECL_CONTEXT() of the global variables _AND_ of all 3081 the temporary variables that might have been generated in the 3082 accompagning initialisers is NULL_TREE, meaning the variables have been 3083 declared in the global namespace. 3084 What we want to do here is to fix that and make sure the DECL_CONTEXT() 3085 of the temporaries are set to the current function decl. */ 3086 cp_walk_tree_without_duplicates (&init, 3087 fix_temporary_vars_context_r, 3088 NULL); 3089 3090 /* Because of: 3091 3092 [class.access.spec] 3093 3094 Access control for implicit calls to the constructors, 3095 the conversion functions, or the destructor called to 3096 create and destroy a static data member is performed as 3097 if these calls appeared in the scope of the member's 3098 class. 3099 3100 we pretend we are in a static member function of the class of 3101 which the DECL is a member. */ 3102 if (member_p (decl)) 3103 { 3104 DECL_CONTEXT (current_function_decl) = DECL_CONTEXT (decl); 3105 DECL_STATIC_FUNCTION_P (current_function_decl) = 1; 3106 } 3107 3108 /* Assume we don't need a guard. */ 3109 guard = NULL_TREE; 3110 /* We need a guard if this is an object with external linkage that 3111 might be initialized in more than one place. (For example, a 3112 static data member of a template, when the data member requires 3113 construction.) */ 3114 if (NEEDS_GUARD_P (decl)) 3115 { 3116 tree guard_cond; 3117 3118 guard = get_guard (decl); 3119 3120 /* When using __cxa_atexit, we just check the GUARD as we would 3121 for a local static. */ 3122 if (flag_use_cxa_atexit) 3123 { 3124 /* When using __cxa_atexit, we never try to destroy 3125 anything from a static destructor. */ 3126 gcc_assert (initp); 3127 guard_cond = get_guard_cond (guard); 3128 } 3129 /* If we don't have __cxa_atexit, then we will be running 3130 destructors from .fini sections, or their equivalents. So, 3131 we need to know how many times we've tried to initialize this 3132 object. We do initializations only if the GUARD is zero, 3133 i.e., if we are the first to initialize the variable. We do 3134 destructions only if the GUARD is one, i.e., if we are the 3135 last to destroy the variable. */ 3136 else if (initp) 3137 guard_cond 3138 = cp_build_binary_op (input_location, 3139 EQ_EXPR, 3140 cp_build_unary_op (PREINCREMENT_EXPR, 3141 guard, 3142 /*noconvert=*/1, 3143 tf_warning_or_error), 3144 integer_one_node, 3145 tf_warning_or_error); 3146 else 3147 guard_cond 3148 = cp_build_binary_op (input_location, 3149 EQ_EXPR, 3150 cp_build_unary_op (PREDECREMENT_EXPR, 3151 guard, 3152 /*noconvert=*/1, 3153 tf_warning_or_error), 3154 integer_zero_node, 3155 tf_warning_or_error); 3156 3157 guard_if_stmt = begin_if_stmt (); 3158 finish_if_stmt_cond (guard_cond, guard_if_stmt); 3159 } 3160 3161 3162 /* If we're using __cxa_atexit, we have not already set the GUARD, 3163 so we must do so now. */ 3164 if (guard && initp && flag_use_cxa_atexit) 3165 finish_expr_stmt (set_guard (guard)); 3166 3167 /* Perform the initialization or destruction. */ 3168 if (initp) 3169 { 3170 if (init) 3171 finish_expr_stmt (init); 3172 3173 /* If we're using __cxa_atexit, register a function that calls the 3174 destructor for the object. */ 3175 if (flag_use_cxa_atexit) 3176 finish_expr_stmt (register_dtor_fn (decl)); 3177 } 3178 else 3179 finish_expr_stmt (build_cleanup (decl)); 3180 3181 /* Finish the guard if-stmt, if necessary. */ 3182 if (guard) 3183 { 3184 finish_then_clause (guard_if_stmt); 3185 finish_if_stmt (guard_if_stmt); 3186 } 3187 3188 /* Now that we're done with DECL we don't need to pretend to be a 3189 member of its class any longer. */ 3190 DECL_CONTEXT (current_function_decl) = NULL_TREE; 3191 DECL_STATIC_FUNCTION_P (current_function_decl) = 0; 3192 } 3193 3194 /* Generate code to do the initialization or destruction of the decls in VARS, 3195 a TREE_LIST of VAR_DECL with static storage duration. 3196 Whether initialization or destruction is performed is specified by INITP. */ 3197 3198 static void 3199 do_static_initialization_or_destruction (tree vars, bool initp) 3200 { 3201 tree node, init_if_stmt, cond; 3202 3203 /* Build the outer if-stmt to check for initialization or destruction. */ 3204 init_if_stmt = begin_if_stmt (); 3205 cond = initp ? integer_one_node : integer_zero_node; 3206 cond = cp_build_binary_op (input_location, 3207 EQ_EXPR, 3208 initialize_p_decl, 3209 cond, 3210 tf_warning_or_error); 3211 finish_if_stmt_cond (cond, init_if_stmt); 3212 3213 node = vars; 3214 do { 3215 tree decl = TREE_VALUE (node); 3216 tree priority_if_stmt; 3217 int priority; 3218 priority_info pi; 3219 3220 /* If we don't need a destructor, there's nothing to do. Avoid 3221 creating a possibly empty if-stmt. */ 3222 if (!initp && TYPE_HAS_TRIVIAL_DESTRUCTOR (TREE_TYPE (decl))) 3223 { 3224 node = TREE_CHAIN (node); 3225 continue; 3226 } 3227 3228 /* Remember that we had an initialization or finalization at this 3229 priority. */ 3230 priority = DECL_EFFECTIVE_INIT_PRIORITY (decl); 3231 pi = get_priority_info (priority); 3232 if (initp) 3233 pi->initializations_p = 1; 3234 else 3235 pi->destructions_p = 1; 3236 3237 /* Conditionalize this initialization on being in the right priority 3238 and being initializing/finalizing appropriately. */ 3239 priority_if_stmt = begin_if_stmt (); 3240 cond = cp_build_binary_op (input_location, 3241 EQ_EXPR, 3242 priority_decl, 3243 build_int_cst (NULL_TREE, priority), 3244 tf_warning_or_error); 3245 finish_if_stmt_cond (cond, priority_if_stmt); 3246 3247 /* Process initializers with same priority. */ 3248 for (; node 3249 && DECL_EFFECTIVE_INIT_PRIORITY (TREE_VALUE (node)) == priority; 3250 node = TREE_CHAIN (node)) 3251 /* Do one initialization or destruction. */ 3252 one_static_initialization_or_destruction (TREE_VALUE (node), 3253 TREE_PURPOSE (node), initp); 3254 3255 /* Finish up the priority if-stmt body. */ 3256 finish_then_clause (priority_if_stmt); 3257 finish_if_stmt (priority_if_stmt); 3258 3259 } while (node); 3260 3261 /* Finish up the init/destruct if-stmt body. */ 3262 finish_then_clause (init_if_stmt); 3263 finish_if_stmt (init_if_stmt); 3264 } 3265 3266 /* VARS is a list of variables with static storage duration which may 3267 need initialization and/or finalization. Remove those variables 3268 that don't really need to be initialized or finalized, and return 3269 the resulting list. The order in which the variables appear in 3270 VARS is in reverse order of the order in which they should actually 3271 be initialized. The list we return is in the unreversed order; 3272 i.e., the first variable should be initialized first. */ 3273 3274 static tree 3275 prune_vars_needing_no_initialization (tree *vars) 3276 { 3277 tree *var = vars; 3278 tree result = NULL_TREE; 3279 3280 while (*var) 3281 { 3282 tree t = *var; 3283 tree decl = TREE_VALUE (t); 3284 tree init = TREE_PURPOSE (t); 3285 3286 /* Deal gracefully with error. */ 3287 if (decl == error_mark_node) 3288 { 3289 var = &TREE_CHAIN (t); 3290 continue; 3291 } 3292 3293 /* The only things that can be initialized are variables. */ 3294 gcc_assert (TREE_CODE (decl) == VAR_DECL); 3295 3296 /* If this object is not defined, we don't need to do anything 3297 here. */ 3298 if (DECL_EXTERNAL (decl)) 3299 { 3300 var = &TREE_CHAIN (t); 3301 continue; 3302 } 3303 3304 /* Also, if the initializer already contains errors, we can bail 3305 out now. */ 3306 if (init && TREE_CODE (init) == TREE_LIST 3307 && value_member (error_mark_node, init)) 3308 { 3309 var = &TREE_CHAIN (t); 3310 continue; 3311 } 3312 3313 /* This variable is going to need initialization and/or 3314 finalization, so we add it to the list. */ 3315 *var = TREE_CHAIN (t); 3316 TREE_CHAIN (t) = result; 3317 result = t; 3318 } 3319 3320 return result; 3321 } 3322 3323 /* Make sure we have told the back end about all the variables in 3324 VARS. */ 3325 3326 static void 3327 write_out_vars (tree vars) 3328 { 3329 tree v; 3330 3331 for (v = vars; v; v = TREE_CHAIN (v)) 3332 { 3333 tree var = TREE_VALUE (v); 3334 if (!var_finalized_p (var)) 3335 { 3336 import_export_decl (var); 3337 rest_of_decl_compilation (var, 1, 1); 3338 } 3339 } 3340 } 3341 3342 /* Generate a static constructor (if CONSTRUCTOR_P) or destructor 3343 (otherwise) that will initialize all global objects with static 3344 storage duration having the indicated PRIORITY. */ 3345 3346 static void 3347 generate_ctor_or_dtor_function (bool constructor_p, int priority, 3348 location_t *locus) 3349 { 3350 char function_key; 3351 tree fndecl; 3352 tree body; 3353 size_t i; 3354 3355 input_location = *locus; 3356 /* ??? */ 3357 /* Was: locus->line++; */ 3358 3359 /* We use `I' to indicate initialization and `D' to indicate 3360 destruction. */ 3361 function_key = constructor_p ? 'I' : 'D'; 3362 3363 /* We emit the function lazily, to avoid generating empty 3364 global constructors and destructors. */ 3365 body = NULL_TREE; 3366 3367 /* For Objective-C++, we may need to initialize metadata found in this module. 3368 This must be done _before_ any other static initializations. */ 3369 if (c_dialect_objc () && (priority == DEFAULT_INIT_PRIORITY) 3370 && constructor_p && objc_static_init_needed_p ()) 3371 { 3372 body = start_objects (function_key, priority); 3373 objc_generate_static_init_call (NULL_TREE); 3374 } 3375 3376 /* Call the static storage duration function with appropriate 3377 arguments. */ 3378 FOR_EACH_VEC_ELT (tree, ssdf_decls, i, fndecl) 3379 { 3380 /* Calls to pure or const functions will expand to nothing. */ 3381 if (! (flags_from_decl_or_type (fndecl) & (ECF_CONST | ECF_PURE))) 3382 { 3383 tree call; 3384 3385 if (! body) 3386 body = start_objects (function_key, priority); 3387 3388 call = cp_build_function_call_nary (fndecl, tf_warning_or_error, 3389 build_int_cst (NULL_TREE, 3390 constructor_p), 3391 build_int_cst (NULL_TREE, 3392 priority), 3393 NULL_TREE); 3394 finish_expr_stmt (call); 3395 } 3396 } 3397 3398 /* Close out the function. */ 3399 if (body) 3400 finish_objects (function_key, priority, body); 3401 } 3402 3403 /* Generate constructor and destructor functions for the priority 3404 indicated by N. */ 3405 3406 static int 3407 generate_ctor_and_dtor_functions_for_priority (splay_tree_node n, void * data) 3408 { 3409 location_t *locus = (location_t *) data; 3410 int priority = (int) n->key; 3411 priority_info pi = (priority_info) n->value; 3412 3413 /* Generate the functions themselves, but only if they are really 3414 needed. */ 3415 if (pi->initializations_p) 3416 generate_ctor_or_dtor_function (/*constructor_p=*/true, priority, locus); 3417 if (pi->destructions_p) 3418 generate_ctor_or_dtor_function (/*constructor_p=*/false, priority, locus); 3419 3420 /* Keep iterating. */ 3421 return 0; 3422 } 3423 3424 /* Called via LANGHOOK_CALLGRAPH_ANALYZE_EXPR. It is supposed to mark 3425 decls referenced from front-end specific constructs; it will be called 3426 only for language-specific tree nodes. 3427 3428 Here we must deal with member pointers. */ 3429 3430 tree 3431 cxx_callgraph_analyze_expr (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED) 3432 { 3433 tree t = *tp; 3434 3435 switch (TREE_CODE (t)) 3436 { 3437 case PTRMEM_CST: 3438 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (t))) 3439 cgraph_mark_address_taken_node ( 3440 cgraph_get_create_node (PTRMEM_CST_MEMBER (t))); 3441 break; 3442 case BASELINK: 3443 if (TREE_CODE (BASELINK_FUNCTIONS (t)) == FUNCTION_DECL) 3444 cgraph_mark_address_taken_node ( 3445 cgraph_get_create_node (BASELINK_FUNCTIONS (t))); 3446 break; 3447 case VAR_DECL: 3448 if (DECL_CONTEXT (t) 3449 && flag_use_repository 3450 && TREE_CODE (DECL_CONTEXT (t)) == FUNCTION_DECL) 3451 /* If we need a static variable in a function, then we 3452 need the containing function. */ 3453 mark_decl_referenced (DECL_CONTEXT (t)); 3454 break; 3455 default: 3456 break; 3457 } 3458 3459 return NULL; 3460 } 3461 3462 /* Java requires that we be able to reference a local address for a 3463 method, and not be confused by PLT entries. If hidden aliases are 3464 supported, collect and return all the functions for which we should 3465 emit a hidden alias. */ 3466 3467 static struct pointer_set_t * 3468 collect_candidates_for_java_method_aliases (void) 3469 { 3470 struct cgraph_node *node; 3471 struct pointer_set_t *candidates = NULL; 3472 3473 #ifndef HAVE_GAS_HIDDEN 3474 return candidates; 3475 #endif 3476 3477 for (node = cgraph_nodes; node ; node = node->next) 3478 { 3479 tree fndecl = node->decl; 3480 3481 if (DECL_CONTEXT (fndecl) 3482 && TYPE_P (DECL_CONTEXT (fndecl)) 3483 && TYPE_FOR_JAVA (DECL_CONTEXT (fndecl)) 3484 && TARGET_USE_LOCAL_THUNK_ALIAS_P (fndecl)) 3485 { 3486 if (candidates == NULL) 3487 candidates = pointer_set_create (); 3488 pointer_set_insert (candidates, fndecl); 3489 } 3490 } 3491 3492 return candidates; 3493 } 3494 3495 3496 /* Java requires that we be able to reference a local address for a 3497 method, and not be confused by PLT entries. If hidden aliases are 3498 supported, emit one for each java function that we've emitted. 3499 CANDIDATES is the set of FUNCTION_DECLs that were gathered 3500 by collect_candidates_for_java_method_aliases. */ 3501 3502 static void 3503 build_java_method_aliases (struct pointer_set_t *candidates) 3504 { 3505 struct cgraph_node *node; 3506 3507 #ifndef HAVE_GAS_HIDDEN 3508 return; 3509 #endif 3510 3511 for (node = cgraph_nodes; node ; node = node->next) 3512 { 3513 tree fndecl = node->decl; 3514 3515 if (TREE_ASM_WRITTEN (fndecl) 3516 && pointer_set_contains (candidates, fndecl)) 3517 { 3518 /* Mangle the name in a predictable way; we need to reference 3519 this from a java compiled object file. */ 3520 tree oid, nid, alias; 3521 const char *oname; 3522 char *nname; 3523 3524 oid = DECL_ASSEMBLER_NAME (fndecl); 3525 oname = IDENTIFIER_POINTER (oid); 3526 gcc_assert (oname[0] == '_' && oname[1] == 'Z'); 3527 nname = ACONCAT (("_ZGA", oname+2, NULL)); 3528 nid = get_identifier (nname); 3529 3530 alias = make_alias_for (fndecl, nid); 3531 TREE_PUBLIC (alias) = 1; 3532 DECL_VISIBILITY (alias) = VISIBILITY_HIDDEN; 3533 3534 assemble_alias (alias, oid); 3535 } 3536 } 3537 } 3538 3539 /* Return C++ property of T, based on given operation OP. */ 3540 3541 static int 3542 cpp_check (tree t, cpp_operation op) 3543 { 3544 switch (op) 3545 { 3546 case IS_ABSTRACT: 3547 return DECL_PURE_VIRTUAL_P (t); 3548 case IS_CONSTRUCTOR: 3549 return DECL_CONSTRUCTOR_P (t); 3550 case IS_DESTRUCTOR: 3551 return DECL_DESTRUCTOR_P (t); 3552 case IS_COPY_CONSTRUCTOR: 3553 return DECL_COPY_CONSTRUCTOR_P (t); 3554 case IS_TEMPLATE: 3555 return TREE_CODE (t) == TEMPLATE_DECL; 3556 default: 3557 return 0; 3558 } 3559 } 3560 3561 /* Collect source file references recursively, starting from NAMESPC. */ 3562 3563 static void 3564 collect_source_refs (tree namespc) 3565 { 3566 tree t; 3567 3568 if (!namespc) 3569 return; 3570 3571 /* Iterate over names in this name space. */ 3572 for (t = NAMESPACE_LEVEL (namespc)->names; t; t = TREE_CHAIN (t)) 3573 if (!DECL_IS_BUILTIN (t) ) 3574 collect_source_ref (DECL_SOURCE_FILE (t)); 3575 3576 /* Dump siblings, if any */ 3577 collect_source_refs (TREE_CHAIN (namespc)); 3578 3579 /* Dump children, if any */ 3580 collect_source_refs (NAMESPACE_LEVEL (namespc)->namespaces); 3581 } 3582 3583 /* Collect decls relevant to SOURCE_FILE from all namespaces recursively, 3584 starting from NAMESPC. */ 3585 3586 static void 3587 collect_ada_namespace (tree namespc, const char *source_file) 3588 { 3589 if (!namespc) 3590 return; 3591 3592 /* Collect decls from this namespace */ 3593 collect_ada_nodes (NAMESPACE_LEVEL (namespc)->names, source_file); 3594 3595 /* Collect siblings, if any */ 3596 collect_ada_namespace (TREE_CHAIN (namespc), source_file); 3597 3598 /* Collect children, if any */ 3599 collect_ada_namespace (NAMESPACE_LEVEL (namespc)->namespaces, source_file); 3600 } 3601 3602 /* Returns true iff there is a definition available for variable or 3603 function DECL. */ 3604 3605 static bool 3606 decl_defined_p (tree decl) 3607 { 3608 if (TREE_CODE (decl) == FUNCTION_DECL) 3609 return (DECL_INITIAL (decl) != NULL_TREE); 3610 else 3611 { 3612 gcc_assert (TREE_CODE (decl) == VAR_DECL); 3613 return !DECL_EXTERNAL (decl); 3614 } 3615 } 3616 3617 /* Nonzero for a VAR_DECL whose value can be used in a constant expression. 3618 3619 [expr.const] 3620 3621 An integral constant-expression can only involve ... const 3622 variables of integral or enumeration types initialized with 3623 constant expressions ... 3624 3625 C++0x also allows constexpr variables and temporaries initialized 3626 with constant expressions. We handle the former here, but the latter 3627 are just folded away in cxx_eval_constant_expression. 3628 3629 The standard does not require that the expression be non-volatile. 3630 G++ implements the proposed correction in DR 457. */ 3631 3632 bool 3633 decl_constant_var_p (tree decl) 3634 { 3635 if (!decl_maybe_constant_var_p (decl)) 3636 return false; 3637 3638 /* We don't know if a template static data member is initialized with 3639 a constant expression until we instantiate its initializer. Even 3640 in the case of a constexpr variable, we can't treat it as a 3641 constant until its initializer is complete in case it's used in 3642 its own initializer. */ 3643 mark_used (decl); 3644 return DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl); 3645 } 3646 3647 /* Returns true if DECL could be a symbolic constant variable, depending on 3648 its initializer. */ 3649 3650 bool 3651 decl_maybe_constant_var_p (tree decl) 3652 { 3653 tree type = TREE_TYPE (decl); 3654 if (TREE_CODE (decl) != VAR_DECL) 3655 return false; 3656 if (DECL_DECLARED_CONSTEXPR_P (decl)) 3657 return true; 3658 return (CP_TYPE_CONST_NON_VOLATILE_P (type) 3659 && INTEGRAL_OR_ENUMERATION_TYPE_P (type)); 3660 } 3661 3662 /* Complain that DECL uses a type with no linkage but is never defined. */ 3663 3664 static void 3665 no_linkage_error (tree decl) 3666 { 3667 tree t = no_linkage_check (TREE_TYPE (decl), /*relaxed_p=*/false); 3668 if (TYPE_ANONYMOUS_P (t)) 3669 { 3670 permerror (0, "%q+#D, declared using anonymous type, " 3671 "is used but never defined", decl); 3672 if (is_typedef_decl (TYPE_NAME (t))) 3673 permerror (0, "%q+#D does not refer to the unqualified type, " 3674 "so it is not used for linkage", TYPE_NAME (t)); 3675 } 3676 else 3677 permerror (0, "%q+#D, declared using local type %qT, " 3678 "is used but never defined", decl, t); 3679 } 3680 3681 /* Collect declarations from all namespaces relevant to SOURCE_FILE. */ 3682 3683 static void 3684 collect_all_refs (const char *source_file) 3685 { 3686 collect_ada_namespace (global_namespace, source_file); 3687 } 3688 3689 /* Clear DECL_EXTERNAL for NODE. */ 3690 3691 static bool 3692 clear_decl_external (struct cgraph_node *node, void *data ATTRIBUTE_UNUSED) 3693 { 3694 DECL_EXTERNAL (node->decl) = 0; 3695 return false; 3696 } 3697 3698 /* This routine is called at the end of compilation. 3699 Its job is to create all the code needed to initialize and 3700 destroy the global aggregates. We do the destruction 3701 first, since that way we only need to reverse the decls once. */ 3702 3703 void 3704 cp_write_global_declarations (void) 3705 { 3706 tree vars; 3707 bool reconsider; 3708 size_t i; 3709 location_t locus; 3710 unsigned ssdf_count = 0; 3711 int retries = 0; 3712 tree decl; 3713 struct pointer_set_t *candidates; 3714 3715 locus = input_location; 3716 at_eof = 1; 3717 3718 /* Bad parse errors. Just forget about it. */ 3719 if (! global_bindings_p () || current_class_type 3720 || !VEC_empty (tree,decl_namespace_list)) 3721 return; 3722 3723 if (pch_file) 3724 c_common_write_pch (); 3725 3726 cgraph_process_same_body_aliases (); 3727 3728 /* Handle -fdump-ada-spec[-slim] */ 3729 if (dump_enabled_p (TDI_ada)) 3730 { 3731 if (get_dump_file_info (TDI_ada)->flags & TDF_SLIM) 3732 collect_source_ref (main_input_filename); 3733 else 3734 collect_source_refs (global_namespace); 3735 3736 dump_ada_specs (collect_all_refs, cpp_check); 3737 } 3738 3739 /* FIXME - huh? was input_line -= 1;*/ 3740 3741 timevar_start (TV_PHASE_DEFERRED); 3742 3743 /* We now have to write out all the stuff we put off writing out. 3744 These include: 3745 3746 o Template specializations that we have not yet instantiated, 3747 but which are needed. 3748 o Initialization and destruction for non-local objects with 3749 static storage duration. (Local objects with static storage 3750 duration are initialized when their scope is first entered, 3751 and are cleaned up via atexit.) 3752 o Virtual function tables. 3753 3754 All of these may cause others to be needed. For example, 3755 instantiating one function may cause another to be needed, and 3756 generating the initializer for an object may cause templates to be 3757 instantiated, etc., etc. */ 3758 3759 emit_support_tinfos (); 3760 3761 do 3762 { 3763 tree t; 3764 tree decl; 3765 3766 reconsider = false; 3767 3768 /* If there are templates that we've put off instantiating, do 3769 them now. */ 3770 instantiate_pending_templates (retries); 3771 ggc_collect (); 3772 3773 /* Write out virtual tables as required. Note that writing out 3774 the virtual table for a template class may cause the 3775 instantiation of members of that class. If we write out 3776 vtables then we remove the class from our list so we don't 3777 have to look at it again. */ 3778 3779 while (keyed_classes != NULL_TREE 3780 && maybe_emit_vtables (TREE_VALUE (keyed_classes))) 3781 { 3782 reconsider = true; 3783 keyed_classes = TREE_CHAIN (keyed_classes); 3784 } 3785 3786 t = keyed_classes; 3787 if (t != NULL_TREE) 3788 { 3789 tree next = TREE_CHAIN (t); 3790 3791 while (next) 3792 { 3793 if (maybe_emit_vtables (TREE_VALUE (next))) 3794 { 3795 reconsider = true; 3796 TREE_CHAIN (t) = TREE_CHAIN (next); 3797 } 3798 else 3799 t = next; 3800 3801 next = TREE_CHAIN (t); 3802 } 3803 } 3804 3805 /* Write out needed type info variables. We have to be careful 3806 looping through unemitted decls, because emit_tinfo_decl may 3807 cause other variables to be needed. New elements will be 3808 appended, and we remove from the vector those that actually 3809 get emitted. */ 3810 for (i = VEC_length (tree, unemitted_tinfo_decls); 3811 VEC_iterate (tree, unemitted_tinfo_decls, --i, t);) 3812 if (emit_tinfo_decl (t)) 3813 { 3814 reconsider = true; 3815 VEC_unordered_remove (tree, unemitted_tinfo_decls, i); 3816 } 3817 3818 /* The list of objects with static storage duration is built up 3819 in reverse order. We clear STATIC_AGGREGATES so that any new 3820 aggregates added during the initialization of these will be 3821 initialized in the correct order when we next come around the 3822 loop. */ 3823 vars = prune_vars_needing_no_initialization (&static_aggregates); 3824 3825 if (vars) 3826 { 3827 /* We need to start a new initialization function each time 3828 through the loop. That's because we need to know which 3829 vtables have been referenced, and TREE_SYMBOL_REFERENCED 3830 isn't computed until a function is finished, and written 3831 out. That's a deficiency in the back end. When this is 3832 fixed, these initialization functions could all become 3833 inline, with resulting performance improvements. */ 3834 tree ssdf_body; 3835 3836 /* Set the line and file, so that it is obviously not from 3837 the source file. */ 3838 input_location = locus; 3839 ssdf_body = start_static_storage_duration_function (ssdf_count); 3840 3841 /* Make sure the back end knows about all the variables. */ 3842 write_out_vars (vars); 3843 3844 /* First generate code to do all the initializations. */ 3845 if (vars) 3846 do_static_initialization_or_destruction (vars, /*initp=*/true); 3847 3848 /* Then, generate code to do all the destructions. Do these 3849 in reverse order so that the most recently constructed 3850 variable is the first destroyed. If we're using 3851 __cxa_atexit, then we don't need to do this; functions 3852 were registered at initialization time to destroy the 3853 local statics. */ 3854 if (!flag_use_cxa_atexit && vars) 3855 { 3856 vars = nreverse (vars); 3857 do_static_initialization_or_destruction (vars, /*initp=*/false); 3858 } 3859 else 3860 vars = NULL_TREE; 3861 3862 /* Finish up the static storage duration function for this 3863 round. */ 3864 input_location = locus; 3865 finish_static_storage_duration_function (ssdf_body); 3866 3867 /* All those initializations and finalizations might cause 3868 us to need more inline functions, more template 3869 instantiations, etc. */ 3870 reconsider = true; 3871 ssdf_count++; 3872 /* ??? was: locus.line++; */ 3873 } 3874 3875 /* Go through the set of inline functions whose bodies have not 3876 been emitted yet. If out-of-line copies of these functions 3877 are required, emit them. */ 3878 FOR_EACH_VEC_ELT (tree, deferred_fns, i, decl) 3879 { 3880 /* Does it need synthesizing? */ 3881 if (DECL_DEFAULTED_FN (decl) && ! DECL_INITIAL (decl) 3882 && (! DECL_REALLY_EXTERN (decl) || possibly_inlined_p (decl))) 3883 { 3884 /* Even though we're already at the top-level, we push 3885 there again. That way, when we pop back a few lines 3886 hence, all of our state is restored. Otherwise, 3887 finish_function doesn't clean things up, and we end 3888 up with CURRENT_FUNCTION_DECL set. */ 3889 push_to_top_level (); 3890 /* The decl's location will mark where it was first 3891 needed. Save that so synthesize method can indicate 3892 where it was needed from, in case of error */ 3893 input_location = DECL_SOURCE_LOCATION (decl); 3894 synthesize_method (decl); 3895 pop_from_top_level (); 3896 reconsider = true; 3897 } 3898 3899 if (!DECL_SAVED_TREE (decl)) 3900 continue; 3901 3902 /* We lie to the back end, pretending that some functions 3903 are not defined when they really are. This keeps these 3904 functions from being put out unnecessarily. But, we must 3905 stop lying when the functions are referenced, or if they 3906 are not comdat since they need to be put out now. If 3907 DECL_INTERFACE_KNOWN, then we have already set 3908 DECL_EXTERNAL appropriately, so there's no need to check 3909 again, and we do not want to clear DECL_EXTERNAL if a 3910 previous call to import_export_decl set it. 3911 3912 This is done in a separate for cycle, because if some 3913 deferred function is contained in another deferred 3914 function later in deferred_fns varray, 3915 rest_of_compilation would skip this function and we 3916 really cannot expand the same function twice. */ 3917 import_export_decl (decl); 3918 if (DECL_NOT_REALLY_EXTERN (decl) 3919 && DECL_INITIAL (decl) 3920 && decl_needed_p (decl)) 3921 { 3922 struct cgraph_node *node, *next; 3923 3924 node = cgraph_get_node (decl); 3925 if (node->same_body_alias) 3926 node = cgraph_alias_aliased_node (node); 3927 3928 cgraph_for_node_and_aliases (node, clear_decl_external, 3929 NULL, true); 3930 /* If we mark !DECL_EXTERNAL one of the symbols in some comdat 3931 group, we need to mark all symbols in the same comdat group 3932 that way. */ 3933 if (node->same_comdat_group) 3934 for (next = node->same_comdat_group; 3935 next != node; 3936 next = next->same_comdat_group) 3937 cgraph_for_node_and_aliases (next, clear_decl_external, 3938 NULL, true); 3939 } 3940 3941 /* If we're going to need to write this function out, and 3942 there's already a body for it, create RTL for it now. 3943 (There might be no body if this is a method we haven't 3944 gotten around to synthesizing yet.) */ 3945 if (!DECL_EXTERNAL (decl) 3946 && decl_needed_p (decl) 3947 && !TREE_ASM_WRITTEN (decl) 3948 && !cgraph_get_node (decl)->local.finalized) 3949 { 3950 /* We will output the function; no longer consider it in this 3951 loop. */ 3952 DECL_DEFER_OUTPUT (decl) = 0; 3953 /* Generate RTL for this function now that we know we 3954 need it. */ 3955 expand_or_defer_fn (decl); 3956 /* If we're compiling -fsyntax-only pretend that this 3957 function has been written out so that we don't try to 3958 expand it again. */ 3959 if (flag_syntax_only) 3960 TREE_ASM_WRITTEN (decl) = 1; 3961 reconsider = true; 3962 } 3963 } 3964 3965 if (walk_namespaces (wrapup_globals_for_namespace, /*data=*/0)) 3966 reconsider = true; 3967 3968 /* Static data members are just like namespace-scope globals. */ 3969 FOR_EACH_VEC_ELT (tree, pending_statics, i, decl) 3970 { 3971 if (var_finalized_p (decl) || DECL_REALLY_EXTERN (decl) 3972 /* Don't write it out if we haven't seen a definition. */ 3973 || DECL_IN_AGGR_P (decl)) 3974 continue; 3975 import_export_decl (decl); 3976 /* If this static data member is needed, provide it to the 3977 back end. */ 3978 if (DECL_NOT_REALLY_EXTERN (decl) && decl_needed_p (decl)) 3979 DECL_EXTERNAL (decl) = 0; 3980 } 3981 if (VEC_length (tree, pending_statics) != 0 3982 && wrapup_global_declarations (VEC_address (tree, pending_statics), 3983 VEC_length (tree, pending_statics))) 3984 reconsider = true; 3985 3986 retries++; 3987 } 3988 while (reconsider); 3989 3990 /* All used inline functions must have a definition at this point. */ 3991 FOR_EACH_VEC_ELT (tree, deferred_fns, i, decl) 3992 { 3993 if (/* Check online inline functions that were actually used. */ 3994 DECL_ODR_USED (decl) && DECL_DECLARED_INLINE_P (decl) 3995 /* If the definition actually was available here, then the 3996 fact that the function was not defined merely represents 3997 that for some reason (use of a template repository, 3998 #pragma interface, etc.) we decided not to emit the 3999 definition here. */ 4000 && !DECL_INITIAL (decl) 4001 /* Don't complain if the template was defined. */ 4002 && !(DECL_TEMPLATE_INSTANTIATION (decl) 4003 && DECL_INITIAL (DECL_TEMPLATE_RESULT 4004 (template_for_substitution (decl))))) 4005 { 4006 warning (0, "inline function %q+D used but never defined", decl); 4007 /* Avoid a duplicate warning from check_global_declaration_1. */ 4008 TREE_NO_WARNING (decl) = 1; 4009 } 4010 } 4011 4012 /* So must decls that use a type with no linkage. */ 4013 FOR_EACH_VEC_ELT (tree, no_linkage_decls, i, decl) 4014 if (!decl_defined_p (decl)) 4015 no_linkage_error (decl); 4016 4017 /* Then, do the Objective-C stuff. This is where all the 4018 Objective-C module stuff gets generated (symtab, 4019 class/protocol/selector lists etc). This must be done after C++ 4020 templates, destructors etc. so that selectors used in C++ 4021 templates are properly allocated. */ 4022 if (c_dialect_objc ()) 4023 objc_write_global_declarations (); 4024 4025 /* We give C linkage to static constructors and destructors. */ 4026 push_lang_context (lang_name_c); 4027 4028 /* Generate initialization and destruction functions for all 4029 priorities for which they are required. */ 4030 if (priority_info_map) 4031 splay_tree_foreach (priority_info_map, 4032 generate_ctor_and_dtor_functions_for_priority, 4033 /*data=*/&locus); 4034 else if (c_dialect_objc () && objc_static_init_needed_p ()) 4035 /* If this is obj-c++ and we need a static init, call 4036 generate_ctor_or_dtor_function. */ 4037 generate_ctor_or_dtor_function (/*constructor_p=*/true, 4038 DEFAULT_INIT_PRIORITY, &locus); 4039 4040 /* We're done with the splay-tree now. */ 4041 if (priority_info_map) 4042 splay_tree_delete (priority_info_map); 4043 4044 /* Generate any missing aliases. */ 4045 maybe_apply_pending_pragma_weaks (); 4046 4047 /* We're done with static constructors, so we can go back to "C++" 4048 linkage now. */ 4049 pop_lang_context (); 4050 4051 /* Collect candidates for Java hidden aliases. */ 4052 candidates = collect_candidates_for_java_method_aliases (); 4053 4054 timevar_stop (TV_PHASE_DEFERRED); 4055 timevar_start (TV_PHASE_CGRAPH); 4056 4057 cgraph_finalize_compilation_unit (); 4058 4059 timevar_stop (TV_PHASE_CGRAPH); 4060 timevar_start (TV_PHASE_CHECK_DBGINFO); 4061 4062 /* Now, issue warnings about static, but not defined, functions, 4063 etc., and emit debugging information. */ 4064 walk_namespaces (wrapup_globals_for_namespace, /*data=*/&reconsider); 4065 if (VEC_length (tree, pending_statics) != 0) 4066 { 4067 check_global_declarations (VEC_address (tree, pending_statics), 4068 VEC_length (tree, pending_statics)); 4069 emit_debug_global_declarations (VEC_address (tree, pending_statics), 4070 VEC_length (tree, pending_statics)); 4071 } 4072 4073 perform_deferred_noexcept_checks (); 4074 4075 /* Generate hidden aliases for Java. */ 4076 if (candidates) 4077 { 4078 build_java_method_aliases (candidates); 4079 pointer_set_destroy (candidates); 4080 } 4081 4082 finish_repo (); 4083 4084 /* The entire file is now complete. If requested, dump everything 4085 to a file. */ 4086 { 4087 int flags; 4088 FILE *stream = dump_begin (TDI_tu, &flags); 4089 4090 if (stream) 4091 { 4092 dump_node (global_namespace, flags & ~TDF_SLIM, stream); 4093 dump_end (TDI_tu, stream); 4094 } 4095 } 4096 4097 if (flag_detailed_statistics) 4098 { 4099 dump_tree_statistics (); 4100 dump_time_statistics (); 4101 } 4102 input_location = locus; 4103 4104 #ifdef ENABLE_CHECKING 4105 validate_conversion_obstack (); 4106 #endif /* ENABLE_CHECKING */ 4107 4108 timevar_stop (TV_PHASE_CHECK_DBGINFO); 4109 } 4110 4111 /* FN is an OFFSET_REF, DOTSTAR_EXPR or MEMBER_REF indicating the 4112 function to call in parse-tree form; it has not yet been 4113 semantically analyzed. ARGS are the arguments to the function. 4114 They have already been semantically analyzed. This may change 4115 ARGS. */ 4116 4117 tree 4118 build_offset_ref_call_from_tree (tree fn, VEC(tree,gc) **args) 4119 { 4120 tree orig_fn; 4121 VEC(tree,gc) *orig_args = NULL; 4122 tree expr; 4123 tree object; 4124 4125 orig_fn = fn; 4126 object = TREE_OPERAND (fn, 0); 4127 4128 if (processing_template_decl) 4129 { 4130 gcc_assert (TREE_CODE (fn) == DOTSTAR_EXPR 4131 || TREE_CODE (fn) == MEMBER_REF); 4132 if (type_dependent_expression_p (fn) 4133 || any_type_dependent_arguments_p (*args)) 4134 return build_nt_call_vec (fn, *args); 4135 4136 orig_args = make_tree_vector_copy (*args); 4137 4138 /* Transform the arguments and add the implicit "this" 4139 parameter. That must be done before the FN is transformed 4140 because we depend on the form of FN. */ 4141 make_args_non_dependent (*args); 4142 object = build_non_dependent_expr (object); 4143 if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE) 4144 { 4145 if (TREE_CODE (fn) == DOTSTAR_EXPR) 4146 object = cp_build_addr_expr (object, tf_warning_or_error); 4147 VEC_safe_insert (tree, gc, *args, 0, object); 4148 } 4149 /* Now that the arguments are done, transform FN. */ 4150 fn = build_non_dependent_expr (fn); 4151 } 4152 4153 /* A qualified name corresponding to a bound pointer-to-member is 4154 represented as an OFFSET_REF: 4155 4156 struct B { void g(); }; 4157 void (B::*p)(); 4158 void B::g() { (this->*p)(); } */ 4159 if (TREE_CODE (fn) == OFFSET_REF) 4160 { 4161 tree object_addr = cp_build_addr_expr (object, tf_warning_or_error); 4162 fn = TREE_OPERAND (fn, 1); 4163 fn = get_member_function_from_ptrfunc (&object_addr, fn); 4164 VEC_safe_insert (tree, gc, *args, 0, object_addr); 4165 } 4166 4167 if (CLASS_TYPE_P (TREE_TYPE (fn))) 4168 expr = build_op_call (fn, args, tf_warning_or_error); 4169 else 4170 expr = cp_build_function_call_vec (fn, args, tf_warning_or_error); 4171 if (processing_template_decl && expr != error_mark_node) 4172 expr = build_min_non_dep_call_vec (expr, orig_fn, orig_args); 4173 4174 if (orig_args != NULL) 4175 release_tree_vector (orig_args); 4176 4177 return expr; 4178 } 4179 4180 4181 void 4182 check_default_args (tree x) 4183 { 4184 tree arg = TYPE_ARG_TYPES (TREE_TYPE (x)); 4185 bool saw_def = false; 4186 int i = 0 - (TREE_CODE (TREE_TYPE (x)) == METHOD_TYPE); 4187 for (; arg && arg != void_list_node; arg = TREE_CHAIN (arg), ++i) 4188 { 4189 if (TREE_PURPOSE (arg)) 4190 saw_def = true; 4191 else if (saw_def) 4192 { 4193 error ("default argument missing for parameter %P of %q+#D", i, x); 4194 TREE_PURPOSE (arg) = error_mark_node; 4195 } 4196 } 4197 } 4198 4199 /* Return true if function DECL can be inlined. This is used to force 4200 instantiation of methods that might be interesting for inlining. */ 4201 bool 4202 possibly_inlined_p (tree decl) 4203 { 4204 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL); 4205 if (DECL_UNINLINABLE (decl)) 4206 return false; 4207 if (!optimize || pragma_java_exceptions) 4208 return DECL_DECLARED_INLINE_P (decl); 4209 /* When optimizing, we might inline everything when flatten 4210 attribute or heuristics inlining for size or autoinlining 4211 is used. */ 4212 return true; 4213 } 4214 4215 /* Mark DECL (either a _DECL or a BASELINK) as "used" in the program. 4216 If DECL is a specialization or implicitly declared class member, 4217 generate the actual definition. Return false if something goes 4218 wrong, true otherwise. */ 4219 4220 bool 4221 mark_used (tree decl) 4222 { 4223 /* If DECL is a BASELINK for a single function, then treat it just 4224 like the DECL for the function. Otherwise, if the BASELINK is 4225 for an overloaded function, we don't know which function was 4226 actually used until after overload resolution. */ 4227 if (BASELINK_P (decl)) 4228 { 4229 decl = BASELINK_FUNCTIONS (decl); 4230 if (really_overloaded_fn (decl)) 4231 return true; 4232 decl = OVL_CURRENT (decl); 4233 } 4234 4235 /* Set TREE_USED for the benefit of -Wunused. */ 4236 TREE_USED (decl) = 1; 4237 if (DECL_CLONED_FUNCTION_P (decl)) 4238 TREE_USED (DECL_CLONED_FUNCTION (decl)) = 1; 4239 4240 if (TREE_CODE (decl) == FUNCTION_DECL 4241 && DECL_DELETED_FN (decl)) 4242 { 4243 if (DECL_ARTIFICIAL (decl)) 4244 { 4245 if (DECL_OVERLOADED_OPERATOR_P (decl) == TYPE_EXPR 4246 && LAMBDA_TYPE_P (DECL_CONTEXT (decl))) 4247 { 4248 /* We mark a lambda conversion op as deleted if we can't 4249 generate it properly; see maybe_add_lambda_conv_op. */ 4250 sorry ("converting lambda which uses %<...%> to " 4251 "function pointer"); 4252 return false; 4253 } 4254 } 4255 error ("use of deleted function %qD", decl); 4256 if (!maybe_explain_implicit_delete (decl)) 4257 error_at (DECL_SOURCE_LOCATION (decl), "declared here"); 4258 return false; 4259 } 4260 4261 /* We can only check DECL_ODR_USED on variables or functions with 4262 DECL_LANG_SPECIFIC set, and these are also the only decls that we 4263 might need special handling for. */ 4264 if ((TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != FUNCTION_DECL) 4265 || DECL_LANG_SPECIFIC (decl) == NULL 4266 || DECL_THUNK_P (decl)) 4267 return true; 4268 4269 /* We only want to do this processing once. We don't need to keep trying 4270 to instantiate inline templates, because unit-at-a-time will make sure 4271 we get them compiled before functions that want to inline them. */ 4272 if (DECL_ODR_USED (decl)) 4273 return true; 4274 4275 /* If within finish_function, defer the rest until that function 4276 finishes, otherwise it might recurse. */ 4277 if (defer_mark_used_calls) 4278 { 4279 VEC_safe_push (tree, gc, deferred_mark_used_calls, decl); 4280 return true; 4281 } 4282 4283 if (TREE_CODE (decl) == FUNCTION_DECL) 4284 maybe_instantiate_noexcept (decl); 4285 4286 /* Normally, we can wait until instantiation-time to synthesize DECL. 4287 However, if DECL is a static data member initialized with a constant 4288 or a constexpr function, we need it right now because a reference to 4289 such a data member or a call to such function is not value-dependent. */ 4290 if ((decl_maybe_constant_var_p (decl) 4291 || (TREE_CODE (decl) == FUNCTION_DECL 4292 && DECL_DECLARED_CONSTEXPR_P (decl))) 4293 && DECL_LANG_SPECIFIC (decl) 4294 && DECL_TEMPLATE_INFO (decl) 4295 && !uses_template_parms (DECL_TI_ARGS (decl))) 4296 { 4297 /* Instantiating a function will result in garbage collection. We 4298 must treat this situation as if we were within the body of a 4299 function so as to avoid collecting live data only referenced from 4300 the stack (such as overload resolution candidates). */ 4301 ++function_depth; 4302 instantiate_decl (decl, /*defer_ok=*/false, 4303 /*expl_inst_class_mem_p=*/false); 4304 --function_depth; 4305 } 4306 4307 /* If we don't need a value, then we don't need to synthesize DECL. */ 4308 if (cp_unevaluated_operand != 0) 4309 return true; 4310 4311 if (processing_template_decl) 4312 return true; 4313 4314 /* Check this too in case we're within fold_non_dependent_expr. */ 4315 if (DECL_TEMPLATE_INFO (decl) 4316 && uses_template_parms (DECL_TI_ARGS (decl))) 4317 return true; 4318 4319 DECL_ODR_USED (decl) = 1; 4320 if (DECL_CLONED_FUNCTION_P (decl)) 4321 DECL_ODR_USED (DECL_CLONED_FUNCTION (decl)) = 1; 4322 4323 /* DR 757: A type without linkage shall not be used as the type of a 4324 variable or function with linkage, unless 4325 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or 4326 o the variable or function is not used (3.2 [basic.def.odr]) or is 4327 defined in the same translation unit. */ 4328 if (cxx_dialect > cxx98 4329 && decl_linkage (decl) != lk_none 4330 && !DECL_EXTERN_C_P (decl) 4331 && !DECL_ARTIFICIAL (decl) 4332 && !decl_defined_p (decl) 4333 && no_linkage_check (TREE_TYPE (decl), /*relaxed_p=*/false)) 4334 { 4335 if (is_local_extern (decl)) 4336 /* There's no way to define a local extern, and adding it to 4337 the vector interferes with GC, so give an error now. */ 4338 no_linkage_error (decl); 4339 else 4340 VEC_safe_push (tree, gc, no_linkage_decls, decl); 4341 } 4342 4343 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl) 4344 && !DECL_INITIAL (decl) && !DECL_ARTIFICIAL (decl)) 4345 /* Remember it, so we can check it was defined. */ 4346 note_vague_linkage_fn (decl); 4347 4348 /* Is it a synthesized method that needs to be synthesized? */ 4349 if (TREE_CODE (decl) == FUNCTION_DECL 4350 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl) 4351 && DECL_DEFAULTED_FN (decl) 4352 /* A function defaulted outside the class is synthesized either by 4353 cp_finish_decl or instantiate_decl. */ 4354 && !DECL_DEFAULTED_OUTSIDE_CLASS_P (decl) 4355 && ! DECL_INITIAL (decl)) 4356 { 4357 /* Defer virtual destructors so that thunks get the right 4358 linkage. */ 4359 if (DECL_VIRTUAL_P (decl) && !at_eof) 4360 { 4361 note_vague_linkage_fn (decl); 4362 return true; 4363 } 4364 4365 /* Remember the current location for a function we will end up 4366 synthesizing. Then we can inform the user where it was 4367 required in the case of error. */ 4368 DECL_SOURCE_LOCATION (decl) = input_location; 4369 4370 /* Synthesizing an implicitly defined member function will result in 4371 garbage collection. We must treat this situation as if we were 4372 within the body of a function so as to avoid collecting live data 4373 on the stack (such as overload resolution candidates). 4374 4375 We could just let cp_write_global_declarations handle synthesizing 4376 this function by adding it to deferred_fns, but doing 4377 it at the use site produces better error messages. */ 4378 ++function_depth; 4379 synthesize_method (decl); 4380 --function_depth; 4381 /* If this is a synthesized method we don't need to 4382 do the instantiation test below. */ 4383 } 4384 else if ((TREE_CODE (decl) == FUNCTION_DECL || TREE_CODE (decl) == VAR_DECL) 4385 && DECL_TEMPLATE_INFO (decl) 4386 && (!DECL_EXPLICIT_INSTANTIATION (decl) 4387 || always_instantiate_p (decl))) 4388 /* If this is a function or variable that is an instance of some 4389 template, we now know that we will need to actually do the 4390 instantiation. We check that DECL is not an explicit 4391 instantiation because that is not checked in instantiate_decl. 4392 4393 We put off instantiating functions in order to improve compile 4394 times. Maintaining a stack of active functions is expensive, 4395 and the inliner knows to instantiate any functions it might 4396 need. Therefore, we always try to defer instantiation. */ 4397 { 4398 ++function_depth; 4399 instantiate_decl (decl, /*defer_ok=*/true, 4400 /*expl_inst_class_mem_p=*/false); 4401 --function_depth; 4402 } 4403 4404 return true; 4405 } 4406 4407 #include "gt-cp-decl2.h" 4408